As of this past Thursday, teams are now able to expand their active rosters and carry up to 40 players. September call-ups have been around a very long time, yet it seems like only recently that they've become controversial. Many believe changing the rules in the final month takes away from the postseason races.

R.J. Anderson provided a primer on September call-ups earlier this week. As always, every team called up extra players in recent days. A third catcher, an extra left reliever, an extra bench bat for an NL team, whatever. Teams take advantage of expanded rosters and make sure they have enough bodies for any game situation.

Some call-ups are more interesting than others. Some are top prospects and others are journeymen looking to extend their careers. And truth be told, September call-ups rarely have an impact. Most only get to play in extra innings or blowouts. Francisco Rodriguez was the last true impact September call-up, and he only threw 5 2/3 regular season innings for the 2012 Angels.

Here are the 30 most interesting players -- one per team -- called up since rosters expanded this past Thursday. There are a few familiar names here, but most may only be known by diehards and fans of that particular team.

Arizona Diamondbacks: Socrates Brito

Brito, who appeared in 19 games with the D-Backs earlier this season, gets the nod because Arizona has only called up two players this month: Brito and 28-year-old Triple-A masher Kyle Jensen, who won't be unseating Paul Goldschmidt at first base anytime soon. Brito is potentially in line for regular at-bats even with A.J. Pollock back from his elbow injury. He's been a productive minor league hitter and a fantastic outfield defender who figures to carve out a long-term role with the D-Backs in the near future.

Atlanta Braves: Jed Bradley

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Former first round pick Jed Bradley is trying to get his career back on track with the Braves. USATSI

Atlanta's most interesting call-up this season came a few weeks ago, when they brought up top prospect Dansby Swanson. Like Swanson, Bradley was a first round pick once upon a time, but mechanical issues have plagued him since the Brewers made him the 15th overall pick in 2011. The Braves acquired Bradley in a cash trade this past June, and the left-hander seems to have finally gotten his delivery under control. His low-90s fastball and sinking changeup make him a ground ball machine. Bradley was a nice roll of the dice by the Braves and this month they'll see if they can turn him into something useful.

Baltimore Orioles: Jayson Aquino

Not a very interesting first round of call-ups by the O's. They added a swing man (Tyler Wilson) and a third catcher (Caleb Joseph), both of whom have been up-and-down all season. Aquino, a left-hander who fits best in the bullpen, sits in the low-90s with a dynamite changeup he'll use in any count against any batter. Outside of Zach Britton, the Orioles have gotten only 55 1/3 innings from lefty relievers this season, and 37 1/3 of those belong to pitchers who have since been traded or designated for assignment. September is an opportunity for Aquino to carve out a long-term role with the O's.

Boston Red Sox: Yoan Moncada

Moncada is the best prospect in baseball and the most exciting call-up this month. The Red Sox have already said he will play regularly against right-handers, albeit at third base rather than his usual second base. His first start went well Saturday night, but it's fair to wonder how much Moncada will be able to help right away; players who strike out 30.9 percent of the time in Double-A usually don't make the jump to MLB and instantly dominant. His tools suggest superstardom is in his future though. Everyone has to start somewhere, and Moncada is getting his first taste of the big leagues this month.

Chicago Cubs: Jake Buchanan

The Cubs are another team with a less than stellar crop of call-ups. In fact, Buchanan is their only call-up. (They also activated Joe Smith and Chris Coghlan off the DL.) Buchanan, 26, was a minor league free agent signing who had a nice Triple-A season this year. His pitchability stands out more than his raw stuff, though the Cubs and pitching coach Chris Bosio have a track record of getting pitchers to exceed expectations.

Chicago White Sox: Juan Minaya

The ChiSox love their hard-throwers and Minaya fits the bill perfectly. He's a pure reliever with a lightning quick arm that delivers mid-90s heaters and a hard upper-80s slider. Minaya struck out 47 in 52 minor league innings this season and he'll audition for a spot in the team's 2017 bullpen this month. Chicago claimed him off waivers from the Astros at midseason.

Cincinnati Reds: Robert Stephenson

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Few minor league pitchers have better raw stuff than Robert Stephenson. USATSI

At his best, Stephenson looks like a future ace with three put-away pitches in his upper-90s fastball, curveball, and changeup. More often than not his general lack of command holds him back, however. Stephenson is arguably the Reds top pitching prospect, and after a spot start earlier this season, he's in line for an extended look this September. He'll dazzle on his best days, though there figures to be a learning curve.

Cleveland Indians: Erik Gonzalez

The Indians are a player development machine and their farm system has provided a solution to every problem this year, either with a call-up or trade chips. Gonzalez is a budding super-utility player who has played every position other than pitcher and catcher in the minors, and he can hit too. The only real drawback is his tendency to chase out of the zone. Otherwise the skill set points to a future as a borderline starter or heavily used utility guy. Gonzalez won't wow you, but every team wants a player like this on their roster.

Colorado Rockies: Tom Murphy

I'm not convinced there are 30 catchers in baseball better than Murphy right now. He's a bat-first player but is also a solid defender, and he is clearly the Rockies catcher of the future. Veteran Nick Hundley will be a free agent after the season, so the starting job can be Murphy's as soon as next year. For now he'll have to settle for spot start duty in September. Murphy's power points to 20-plus home runs on the regular going forward, especially in Coors Field.

Detroit Tigers: Joe Mantiply

The Tigers only called up three players and two of them (Buck Farmer and John Hicks) are quintessential up-and-down depth players. Mantiply is a legitimate left-handed relief prospect with some funk in his delivery ...

... and a solid fastball/changeup/slider combination. He held left-handed hitters to a .147/.176/.196 batting line with 41 strikeouts in 109 plate appearances in the minors this season. The Tigers are in the race and manager Brad Ausmus may be hesitant to use the rookie in big situations, so Mantiply's goal this month is to make a good enough impression that he comes to spring training with a real chance to make the team next year.

Houston Astros: Jandel Gustave

Gustave spent some time with the Astros in August after taking a long and winding road to the big leagues. Houston signed him out of the Dominican Republic in 2010, the Red Sox selected him in the 2014 draft and traded him immediately to the Royals, then the Padres claimed him on waivers a few weeks later. San Diego eventually returned Gustave to the Astros as a Rule 5 player.

Gustave throws extremely hard -- he's hit 102 mph in the minors -- and right now the only thing holding him back from being a dominant reliever is the consistency of his slider. It's a devastating swing-and-miss pitch at its best and a cement mixer at its worst. Also, he has a knack for trying to throw harder when he gets into jams, which is not uncommon for young players. If nothing else, Gustave is going to light up the radar gun this month.

Kansas City Royals: Hunter Dozier

Many pundits believed the Royals reached when they selected Dozier with the eighth overall pick in the 2013 draft -- the Dozier pick saved draft bonus pool money for Sean Manaea, who Kansas City selected 34th overall -- and the start of his pro career did not go well. He threw his hitting mechanics out of whack when he tried to hit for more power, but he bounced back this season with 44 doubles and 23 homers in the minors. Dozier is one of the Royals' top prospects and this September call-up is step one in the team's plan to work him into their regular lineup in 2017.

Los Angeles Angels: Alex Meyer

Hands down, the most confusing trade at the deadline was the deal that sent Meyer and Ricky Nolasco to the Angels for Hector Santiago. Two rebuilding teams swapped veteran starters, and the Halos picked up a busted former top prospect in the process. Meyer has been around a long time -- he was a 2011 first round pick and is now 26 -- and he's been held back consistently by shaky mechanics. Pitchers who stand 6-foot-9 usually develop late because their long limbs complicate their deliveries. Meyer has premium stuff and the Angels, who essentially have nothing to lose, will look at him as a starter this month to see if he can begin to put it all together.

Los Angeles Dodgers: Jose De Leon

Jose De Leon will make his MLB debut on Sunday. USATSI

I was tempted to go with Yasiel Puig here, but he's an established big leaguer at this point, and really, I think we're all kind of sick of hearing about him. De Leon, meanwhile, is one of the top pitching prospects in the game, and Sunday he will become the 15th different starter used by the Dodgers in 2016. That's the most in baseball. He's a former 24th round pick who, through hard work and good coaching, has become a top prospect and a potential rotation cornerstone. De Leon struck out 111 and walked only 20 in 86 1/3 Triple-A innings this year.

Miami Marlins: Destin Hood

Hood doubled for his first major league hit Friday night ... then immediately made a baserunning mistake and got caught in a rundown. D'oh! I'll forgive him. Hood was one of my favorite minor league signings of the offseason because he's always had loud tools and a plan at the plate. Injuries slowed him down earlier in his career though. Hood is more of a doubles guy than a home run guy, but he knows the strike zone, can hit to all fields, run well, and play solid defense in all three outfield spots. That's a nice player to stash in Triple-A, and now the 26-year-old Hood is getting his first taste of MLB.

Milwaukee Brewers: Ben Rowen

You know, for a rebuilding team, the Brewers didn't make many interesting call-ups. In fact, Rowen was their only true call-up. (They also activated Jacob Barnes, Junior Guerra, and Michael Blazek off the DL.) The 25-year-old Rowen is a funky submarine reliever who is well-traveled. He's gone from the Rangers to the Dodgers to the Orioles to the Cubs to the Blue Jays to the Brewers since 2014. His minor league numbers are always off-the-charts, but these submarine relievers are tricky to evaluate in the minors. That said, every once in a while one of them turns into Brad Ziegler, so it's a smart move by the Brewers to take a look at Rowen this month.

Minnesota Twins: Byron Buxton

This has been a very difficult season for both the Twins and Buxton. He came into 2016 as one of the two or three best prospects in baseball, but has struggled in two extended big league stints. The Twins sent him down to Triple-A twice -- that seems to be their solution to everything, just send guys down to Triple-A -- and he predictably mashed both times. Buxton is 6 for 10 with two home runs and, most importantly, no strikeouts since being called back up Thursday. It's easy to forget this kid is still only 22 with elite tools. Getting Buxton on track and helping him have a productive September is priority No. 1 for the Twins this month.

New York Mets: Michael Conforto

I have to say, this has been an extremely disappointing season for Conforto, who looked poised to emerge as a middle of the order force after his strong showing last season. Instead, he's struggled so much that he's had to spend two different stints in Triple-A. Conforto's raw hitting tools are outstanding and he still projects to be an impact hitter. He's not the first guy to have a rough sophomore season, after all. The Mets are in the thick of the wild card race and a productive Conforto would be a huge lift, both this month and heading into 2017.

New York Yankees: Luis Severino

The Yankees hoped Severino would emerge as their No. 2 starter behind Masahiro Tanaka this year after his strong late-season cameo last year. Instead, he got hammered in April and May before landing on the DL. Severino has spent the last three months or so shuffling between the Triple-A rotation and MLB bullpen. The Yankees are barely hanging on in the wild card race and they have big time pitching needs, both in the rotation and bullpen. They want Severino to solve one of those problems and show he can be an effective member of their 2017 pitching staff.

Oakland Athletics: Daniel Mengden

The A's acquired Mengden from the Astros in the Scott Kazmir trade and he is everything an Oakland A's pitcher should be. First and foremost, he has a Rollie Fingers-esque mustache. Look at this thing:

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Daniel Mengden and his mustache received a September call-up. USATSI

Outstanding. Secondly, Mengden has an unorthodox delivery that he seems to start, stop, then restart again. Check it out:

Perfect. If you could go into a lab and create an A's pitcher, you'd end up with Mengden. He actually made nine starts earlier this season, and now that it's September, Mengden is back in Oakland with an opportunity to pitch his way into the club's 2017 rotation.

Philadelphia Phillies: Patrick Schuster

Not a very exciting crop of September call-ups for the Phillies. At least not yet, anyway. They may call up some of their top prospects once the minor league playoffs end. For now, Schuster is the most interesting of the bunch as a potential left-on-left matchup guy. He's most famous for throwing four consecutive no-hitters in high school. Schuster made his MLB debut with the A's earlier this season, and this month he'll get a chance to show what can do with the Phillies after being claimed off waivers.

Pittsburgh Pirates: Jason Rogers

The Pirates manipulated their roster well these past few days. They sent Jameson Taillon, Adam Frazier, and Steven Brault to their rookie ball team in Bristol on Tuesday, and since Bristol's season ended Thursday, the Pirates were able to call all three guys back up right away without waiting the usual 10 days. Taillon, Frazier, and Brault are all regular members of the 25-man roster, but Pittsburgh was able to buy some extra roster space for a few days. Smart move to exploit that loophole.

Anyway, Rogers is the one true call-up they've made, and he's a classic utility man who is trying to find a niche on the bench. He was slated to spent the season with the Pirates before they signed David Freese.

San Diego Padres: Leonel Campos

Campos was one of two call-ups the Padres made. The other was lefty reliever Ryan Buchter, who has been the club's best reliever all season. He was sent down with fatigue last month in what appeared to be a service time move. (Fatigued players are supposed to go on the DL, not Triple-A.)

Campos is a classic fastball/slider reliever who has had stints with the Padres the last three years. Usually San Diego has success getting pitchers like this to carve out a role in their bullpen, but it hasn't happened with Campos yet. This September might be his last chance to prove himself with the Padres.

San Francisco Giants: Ty Blach

For all their success the last few seasons, the Giants haven't had much luck developing pitching the last two or three years. There's a reason they've had to go outside the organization to add players like Jake Peavy, Tim Hudson, Mike Leake, Jeff Samardzija, and Johnny Cueto. Blach had the best statistical season of San Francisco's Triple-A starters and projects as a No. 5 starter or swingman. He will likely be limited to long relief this month, but at least he's getting his feet wet. The Giants would love Blach to turn into a useful arm going forward.

Seattle Mariners: Ben Gamel

The Mariners acquired Gamel from the Yankees in a minor trade earlier this week, then added him to the active roster as soon as rosters expanded. He's hit leadoff in his first two games with Seattle too.

Gamel was this year's Triple-A International League MVP, and while that sounds glamorous, it's hardly a predictor of future big league success. The list of recent IL MVPs is quite sad, actually. Still, Gamel has some tools and is a hard-nosed player who plays with the dial turned to 11. For example:

Gamel profiles as a bit of a 'tweener -- not enough power for a corner outfield spot, not enough defense for center -- but he'll be a fan favorite because he plays so damn hard.

St. Louis Cardinals: Carson Kelly

Aside from activating players off the DL, the Cardinals didn't make their first true call-up until Sunday, when they called up Kelly. He was originally drafted as a power-hitting third baseman, but the Cardinals moved him behind the plate almost immediately, and now he's a defense-first backstop. The raw power is still there, but Kelly's offensive development has lagged a bit because he's put so much time in on defense. The Cardinals are fighting for a postseason spot and that means Yadier Molina is going to play pretty much every day this month. The club is simply getting Kelly's feet wet because he figures to play a prominent role in the post-Molina era.

Tampa Bay Rays: Eddie Gamboa

The Rays spent the offseason stockpiling knuckleballers and Gamboa is the first to reach the big leagues. He's a 31-year-old rookie who, like most knuckleballers, started throwing the pitch in an effort to save his career a few years back. Knuckleball pitchers tend to be late bloomers -- both Steven Wright and R.A. Dickey didn't figure it out until after they turned 30 -- which is why you shouldn't write off Gamboa due to his age. Even if he's a swingman, the Rays will give Gamboa a chance to help down the line should he show something positive this month.

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31-year-old knuckleballer Eddie Gamboa is in the big leagues for the first time. USATSI

Texas Rangers: Yohander Mendez

Is he a right-hander or a left-hander? No, he's a Yohander. (Sorry, I had to do it.)

Anyway, Mendez is one of the top pitching prospects in baseball and he had an incredible season in the minors, pitching to a 2.19 ERA with 113 strikeouts in 111 innings while climbing from Single-A to Triple-A. His breaking ball needs a little work and chances are the southpaw will be relegated to mop-up duty this month, but that's okay. Everyone has to start somewhere.

By the way, Mendez was part of the Rangers' incredible 2011 international signing class. They inked Mendez, Rougned Odor, Leonys Martin, Nomar Mazara, and top prospect Ronald Guzman that year.

Toronto Blue Jays: Danny Barnes

Barnes has had a ton of success in the minors as a rare four-pitch reliever. This season he pitched to a 0.73 ERA with 77 strikeouts and six walks in 61 1/3 innings at Double-A and Triple-A, and now he'll try to make an impression on the big league coaching staff in September. Like many rookies this month, Barnes is trying to stand out and put himself in position to make the team out of spring training next year.

Washington Nationals: Pedro Severino

Severino is an interesting prospect because he's a catcher whose glove is far ahead of his bat. He's big league ready defensively right now, and you hate to waste that ability, but his bat could probably use some more minor league seasoning. Starting catcher Wilson Ramos is due to become a free agent this offseason, and while it seems unlikely the Nationals would hand the reins over to Severino next season, he'll at least be in the mix for the backup job.