It is that time of the year again. Time to warn you September callups are notoriously overrated, and then proceed to outline the guys that might help you.

It is a tricky month in Fantasy crunch time. Contenders are pushing for every last bit out of what has gotten them here, while also-rans are searching for someone that might help them get there down the road. With rosters expanding beyond 25-man limits to 30-plus, there are more players to pick through. With the recent additions, though, it is slim pickins. There are too many time-shares, platoons and a finite number of at-bats or starts.

We break down some intriguing names in a few categories: 1. The ones here to play; 2. The ones here to watch; and 3. The ones that could be on their way. No. 3 is a reminder September callups don't stop Sept. 1. They keep coming after the minor-league seasons end -- sometimes after playoff series into the middle of the month.

The ones here to play: These guys are getting handed jobs right away or have a clear path to playing time.

1. Cory Luebke, SP, Padres

We have anticipated the Padres to slow down the stretch -- almost everyone has -- but it has come because the young pitching is reaching its limit. Now, they will turn to one of their top pitching prospects who still has some wiggle room. Oh, Luebke happens to be real good, too. The 2007 first-round pick (Ohio State) made his major-league debut Friday and can stick in the rotation for a contender that takes a seven-game losing streak and a dwindling three-game division lead into the weekend series against Colorado.

Luebke has lost just one game all season, going a combined 10-1 with a 2.68 ERA and .200 batting-average against in 19 games (17 starts) between Double- and Triple-A. That big ballpark in San Diego should help him be a winner for Fantasy owners right away, too. He is owned in just 2 percent of CBSSports.com's leagues and he was less that 1 percent as late as last week. If you have used Padres pitchers other than Mat Latos in your Fantasy lineup this season, you can get some use out of Luebke now.

2. Jenrry Mejia, SP, Mets

"East Coast bias" and the "devil we know vs. the one we don't" have to be the reasons Mejia is owned in 10 percent more leagues than Luebke. Don't get us wrong: Mejia is a great prospect. But, he is not as polished, has a non-contender to pitch for and has already dealt with a sore shoulder for a stretch this summer.

Mejia starts Saturday for the Mets in an effort to lock up a rotation spot heading into spring 2011. He looked like a power-armed prospect out of the bullpen earlier this year and handled starting back down in the minors with ease, going 2-0 with a 1.28 ERA and .200 BAA in nine starts. Most of that damage came in the lower levels, but his one start in Triple-A -- his last -- was an impressive eight innings, five hits, one run, one walk and nine strikeouts.

Unlike Luebke, Mejia is more of a strikeout artist, fanning 45 in 42 1/3 innings, but he also has a less-impressive walk rate. We expect Mejia can be useful, if not dominant, but he will be difficult to trust in Fantasy Week 23 (Sept. 6-12) against a potent offense like the Phillies'. He is going to be someone to watch the matchups with.

3. Brandon Allen, OF/1B, D-Backs

Allen has been around the majors before -- to awful results -- but we have a feeling he is ready to stick this time. It certainly helps he has made the transition to left field, not to mention he made a grand entrance Wednesday night, making a great catch and later hitting a grand slam.

Allen's season started slow due to injury and he was heading back to being that Quadruple-A (great in the minors, unfit for the majors) player he had been labeled. But he turned it on in June and sustained a good run through the final months, going .261-25-86-72-14 (.405-.528). Unlike almost all other September callups, Allen will be in a situation where everyday at-bats will be there for him as long as he can handle them. He certainly looks like he can and will be a popular pickup in deeper leagues, if he hasn't been already.

4. Daniel Espinosa, SS, Nationals

Not excited by this guy? How do these names sound to you: Bobby Crosby, Troy Tulowitzki and Evan Longoria? Those are the Long Beach State shortstops that preceded Espinosa. Some impressive company, save for the out-of-work Crosby.

Espinosa, a third-rounder in 2008, might be more Crosby than Tulo or Longo, but Crosby did win the AL Rookie of the Year way back when. Espinosa is going to add second-base eligibility soon, too, as the Nationals will try to make him their 2B cornerstone with fellow rookie Ian Desmond at shortstop long term.

Espinosa went .264-18-72-90-29 (.375-.460) in his first full season in 2009 and then combined to go .268-22-69-80-25 (.337-.464) between Double- and Triple-A this season. Those are pretty steady levels. He is a must-add in deeper NL-only formats and might even be a factor in deeper mixed leagues if he can get hot and earn everyday duty. He did double in a run in his debut Wednesday.

5. Aroldis Chapman, RP, Reds

One of the 2010 Fantasy busts -- not because he lacks talent, just because he lacked a callup to the rotation -- Chapman is here wowing fans and testing the limits of radar guns everywhere. We know how great he is; it isn't hard to see. But he is limited to a setup role in a pennant race, a La David Price and Francisco Rodriguez of postseasons past.

Chapman's 105 mph fastball gives him a limitless ceiling, but his Fantasy value is limited by his middle-relief role. He might only help deeper Rotisserie leagues.

6. Jeremy Hellickson, SP/RP, Rays

Hell-boy is back, but he will be stuck in the Pitch-22 (good enough to start, but too valuable in relief) now. Sure, Jeff Niemann has been awful since returning from the DL, but the Rays are going to make the postseason with or without an effective back-end starter. They won't go anywhere thereafter without this arm serving an apprenticeship in the late innings.

We do not see Hellickson getting another start this season, but like Chapman, he can help Rotisserie owners even in middle relief. Unlike Chapman, Hellickson sets up for a lock-down closer that almost certainly won't be a candidate to yank from the closer's role either.

7. Lucas Duda, OF, Mets

At 6-foot-5 and 240 pounds, this is a big, big Duda -- sorry, easy pun. The seventh-round pick of the 2007 draft out of the Southern California baseball factory has a legit shot at regular at-bats in left down the stretch for the Mets.

His impressive batting-practice power finally translated into monster numbers this season, going a combined .304-23-87-74-1 (.398-.569) between Double- and Triple-A. Unlike Allen, Duda got the holes in his way ironed out and had a reasonable strikeout rate (84 Ks in 425 at-bats). It wouldn't surprise us if he hits more homers in September than Jason Bay has hit all season (just six). Own him in NL-only formats initially.

8. Lucas May, C, Royals

Jason Kendall's season-ending shoulder surgery comes at a time the Royals' catcher of the future arrives in the majors. May, acquired before the trade deadline for Scott Podsednik, should be able to wrangle full-time duty down the stretch. If his bat can get hot, he could be a nice stopgap at the thin catcher position.

May combined to hit .283 with 16 homers, 59 RBI, 63 runs, four steals, a .349 on-base percentage and .483 slugging percentage in 375 minor-league at-bats. His potential makes him at least a second catcher in AL-only Rotisserie leagues right away.

9. Carlos Carrasco, SP, Indians

Another "devil we know," Carrasco has been unable to translate "stuff" into results. If you watched him Wednesday against the White Sox, you likely came away impressed again, though. Consider him more of an AL-only option, because of the lowly non-contender he pitches for.

Carrasco had a solid season in Triple-A after a slow start, going 10-6 with a 3.68 ERA and a .250 BAA. He struck out 133 batters in 150 1/3 innings. He should be allowed to go over 180 innings, which should set him up to potentially go 200 in his first full season in the majors in 2011.

10. Jeremy Jeffress, RP, Brewers

A 100-game suspension for Performance Enhancing Drugs (PEDs) limited Jeffress to just 32 1/3 innings in relief this season. The 16th-overall pick of the 2006 draft still could be a starter in 2011, but he will serve an apprenticeship in relief down the stretch. He comes with far less fanfare than Chapman or Hellickson, but he could be as productive in Fantasy terms, after posting a 1.26 ERA and .160 BAA in his Double-A stint.

The ones to watch: These are top prospects who are up with contenders or are blocked from regular at-bats. If they get playing time, though, look out.

1. J.P. Arencibia, C, Blue Jays

He arrived with a huge debut in August, but returns likely having to back up John Buck, if not at least share starts. Arencibia is a potential future elite Fantasy catcher after posting a .301-32-85-76-0 (.359-.626) statline in Triple-A Las Vegas, but until he gets full-time at-bats, he will be merely a No. 2 catcher in deeper formats.

We would play him everyday here on out, but unfortunately our name isn't Cito Gaston. Otherwise, Arencibia would be No. 1 above.

2. Desmond Jennings, OF, Rays

The Rays figure to go with veterans, but Jennings could impact AL-only Rotisserie formats even as a reserve. He went .278-3-36-82-37 (.362-.393) in 399 Triple-A at-bats, numbers that were softened by a slow start and a wrist injury that plagued him in the first half. Jennnings could be the Rays' starter in place of free agent Carl Crawford in 2011, but unless he gets real hot, he will be relegated to a bench role this month. It limits his Fantasy value.

3. Freddie Freeman, 1B, Braves

The Braves like Freeman as their likely starter in 2011, but if they liked him as their starter in a pennant race, they wouldn't have been inclined to add Derrek Lee for the stretch run. Lee's presence -- not to mention Troy Glaus' DL return -- figures to make Freeman merely a spot starter. At just 20, the 2007 second-rounder, was impressive in his first season in Triple-A: .319-18-87-73-6 (.378-.521). He could be your 2011 NL Rookie of the Year second choice to Chapman.

4. Mat Gamel, 3B, Brewers

We figured Gamel would already be an impact Fantasy player by now. With the breakthroughs of Rickie Weeks and Casey McGehee in Milwaukee, though -- and Prince Fielder or Corey Hart not getting dealt -- Gamel is stuck behind some big-time Fantasy standouts. Gamel is worthy of regular duty, though, posting a .309-13-67-54-3 (.387-.511) campaign that was limited to 311 minor-league at-bats due to injury. Gamel has pop and will be a regular, but it doesn't look likely down the stretch, if it ever happens in Milwaukee altogether.

5. Yonder Alonso, 1B, Reds

Of all years, Alonso is about as blocked as it gets at first base with NL MVP breakthrough campaign of Joey Votto. Perhaps only Albert Pujols is more of an unmoveable object in baseball. Alonso, the Reds' first-rounder in 2008 (seventh overall), has as much potential as anyone himself, especially with his Triple-A development at .296-12-56-50-9 (.355-.470) in 406 at-bats. A move to left can help, but we doubt a contender trusts him in a pennant race there.

The ones that could be on their way ... (ordered by ownership percentage): They could come up and help out in deeper leagues after their seasons are over.

1. Justin Smoak, 1B, Mariners (24 percent) -- We have to figure he will play every day once he returns. He is their everyday first baseman in 2011.

2. Jesus Montero, C, Yankees (16 percent) -- Jorge Posada likes to catch. Joe Girardi might want Montero more next spring.

3. Kyle Drabek, SP, Blue Jays (15 percent) -- The Blue Jays might give him some spot starts, but the minor-league postseason could get him to his innings limit.

4. Chris V. Carter, OF, A's (15 percent) -- He is on the Triple-A DL and might not be healthy enough to play or help Fantasy owners later this month.

5. Mike Moustakas, 3B, Royals (13 percent) -- He had a huge game recently that might help change the Royals' minds about keeping him down.

6. Chris Tillman, SP, Orioles (13 percent) -- We have seen enough to know he is risky even in deeper leagues, albeit with great stuff.

7. Dustin Ackley, 2B, Mariners (13 percent) -- He is more likely to head to the Arizona Fall League than Fantasy rosters.

8. Yunesky Maya, SP, Nationals (11 percent) -- They want to take a look at him before the season ends, especially with Stephen Strasburg a non-factor in 2011.

9. Michael Taylor, OF, A's (10 percent) -- The A's would be wise to give him a look, because their pitching looks ready to contend.

10. Scott Sizemore, 2B, Tigers (9 percent) -- We have seen enough to know how little he will help us. One of 2010's rookie busts.

Here are some more names that could help in Fantasy if they arrive this month: Mark Trumbo, 1B, Angels; Jared Goedert, 3B, Indians; Dayan Viciedo, 3B, White Sox; Brent Morel, 3B, White Sox; Zach Britton, SP, Orioles; Tanner Scheppers, RP, Rangers; Kyle Gibson, SP, Twins; Simon Castro, SP, Padres; Hank Conger, C, Angels; and Brad Lincoln, SP, Pirates.

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