Red Sox fortify bullpen by trading for Brad Ziegler: Seven things to know

The Red Sox made a move to strengthen the back-end of the bullpen in the wee hours of Saturday morning, trading two prospects to the Diamondbacks in order to acquire right-handed pitcher Brad Ziegler.

Ziegler, 36, has served as the Diamondbacks closer since early in the 2015 season. Despite racking up 48 saves over the last two seasons, he's never profiled as a typical shutdown option in the ninth inning, putting up strikeout rates that would be suspect from a starting pitcher, much less a late-inning relief ace.

Here are seven things to know about this trade and what it means around the league going forward.

1. Ziegler is a very unique pitcher.

If you're new to baseball or simply haven't seen Ziegler pitch all that much, here's some video of him in action:

Part of what keeps hitters off-balance is Ziegler's rare pitch repertoire, which was covered by Eno Sarris in 2014. As FanGraphs illustrated this past offseason, Ziegler's changeup was the hardest pitch in baseball to lay off out of the zone last year. Just the fact that Ziegler throws a changeup at all can be difficult for hitters, as it's not a typical pitch for submariners. (You can see the changeup in the first pitch of the video.) Hitting anything but grounders is hard when you're making contact low and out of the strike zone.

Make no mistake though, Ziegler is a sinkerball pitcher first and foremost. That low arm slot allows him to get great movement and fade on his sinker. Among pitchers with at least 100 innings over the last two years, Ziegler comes in behind only Zach Britton with a 69.2 percent ground ball rate. His 0.3 HR/9 rate ties him with Rich Hill for best in the majors.

So, even though he's recorded only 63 strikeouts in 106 1/3 innings over the last two seasons, Ziegler makes it work, relying on two key traits for success: keeping the ball on the ground and in the ballpark.

2. Kimbrel and Tazawa are hurting.

Notable for Red Sox fans: the trade came on the same night it was revealed that Craig Kimbrel went for an MRI on his sore knee.

The team placed Kimbrel on the disabled list Saturday, announcing the closer will undergo surgery on a torn meniscus and be sidelined for three to six weeks.

Also, seventh-inning man Junichi Tazawa was unavailable Friday with a sore shoulder, so two of Boston's three end-game arms are hurting at the moment. The third, veteran righty Koji Uehara, has a 4.96 ERA in 32 2/3 innings and has allowed eight home runs, including one Friday.

Kimbrel is going to undoubtedly remain in the closer role when healthy, but now Boston has another option for the ninth inning with Kimbrel out. Ziegler's regular role when not closing figures to be as a setup man or as a guy who can come in and get the tough out when needed by keeping batters who likely haven't seen much of him off-balance. He's effectively replacing Carson Smith, who blew out his elbow and needed Tommy John surgery earlier this year.

3. The D-Backs got two decent prospects.

Starting pitcher Jose Almonte, 20, has been in the Red Sox organization for the last four years. Though this year's 3.91 ERA at Class A Greenville is his worst mark in his career, he has made great strides with his control, walking just 2.2 batters per nine innings after posting a 5.2 BB/9 rate last year.

Infielder Luis Alejandro Basabe, 19, is having a productive season at Greenville, hitting .310/.412/.467 with four home runs, 25 RBI and 14 stolen bases in 229 at-bats. His twin brother, Luis Alexander Babase, is an outfielder with a much higher profile, ranking No. 8 on MLB.com's top-30 Red Sox prospects list. Unfortunately for Diamondbacks fans, the identical twins aren't a package deal.

Ziegler's trade value wasn't sky high because he's a rental, he's 36, and he's been more hittable this season than he has been in the past. Arizona was trading maybe 30 innings of the guy, remember. They didn't get a ton in return, opting for two lower-level lottery tickets than one lower upside guy perhaps closer to the majors.

4. Boston still needs a starting pitcher (or two).

With Ziegler and the recently acquired Aaron Hill, the BoSox have shored up two weaknesses in their bullpen and bench. They still have work to do with their rotation, however. Their starters have a 4.84 ERA, ranking 23rd out of the 30 teams. It's also fair to wonder how much longer knuckleballer Steven Wright will sustain his 2.68 ERA given his ultra-low 0.6 HR/9. Knuckleballers have historically been prone to the long ball -- Wright came into 2016 with a career 1.2 HR/9 -- so some negative regression may be coming.

President of baseball operations Dave Dombrowski is a "go for it" type and has a ton of resources at his disposal, both money and prospects. He has the prospect capital to go out and get a high-end starter, say, Julio Teheran or Rich Hill, or he could shoot a little lower for someone like Andrew Cashner or Jeremy Hellickson.

It's not in Dombrowski's nature to shoot low though. He's always been an aggressive buyer. It's not a question of "if" the Red Sox will get another starter, but "when."

5. The D-Backs are sellers.

This trade makes is official: the D-Backs are sellers. They spent all that money to sign Zack Greinke and traded all those young players to get Shelby Miller, and that plan failed, at least for 2016. Arizona comes into Saturday in last place in the NL West at 38-50. They're 17 games back in the division and 10 games back of a wild card spot with eight teams ahead of them. SportsLine puts their postseason odds at 0.0 percent.

I wouldn't go too crazy and expect a Greinke trade or a Paul Goldschmidt trade. Nothing like that will happen. (Never say never, but ... never.) It's more likely GM Dave Stewart will look to unload players like Daniel Hudson, Tyler Clippard, Welington Castillo, and Josh Collmenter than overhaul his roster.

Maybe they'll look to unload Miller or sell high on Jean Segura. Anything bigger than that would surprise me.

6. Ziegler's time with Arizona may not be over.

Ziegler originally broke in with the Athletics back in 2008 before being traded to the D-Backs (for Brandon Allen and Jordan Norberto) at the 2010 trade deadline. He's been in Arizona since. Ziegler and his family presumably have some roots in the area and would be open to returning. The D-Backs would welcome him back:

It takes two to tango, of course. Ziegler has to want to return to the D-Backs as a free agent after the season. He could opt to go to a team he believes has a better chance to win -- Ziegler is 36, after all, and I assume he wants to win a World Series before calling it a career -- or another team could step in and blow him away with an offer. If nothing else, the D-Backs will try to bring him back after the season.

7. There is still a ton of relievers available.

Ziegler is the first reliever domino to fall ahead of the trade deadline. Contenders like the Cubs, Nationals, Dodgers, Giants, Mets, Rangers, Cardinals, Astros, and Indians could all use varying levels of bullpen help at the deadline. Heck, even the Red Sox too. There's always room for another quality reliever.

The bullpen trade market figures to revolve around the Yankees, who, if they decide to sell, could put two elite arms on the market in Andrew Miller and Aroldis Chapman. Chapman is only a rental, but he's still insanely good, so he won't be cheap. Miller has been better than Chapman this year and is signed through 2018 at a very affordable rate.

New York comes into Saturday at 42-44 on the season. They're 5 1/2 games back of a wild card spot with six teams ahead of them. The Yankees have been in contention for the better part of two decades now and selling is not in their DNA, but at this point it has to be seriously considered. Miller and Chapman could bring back a huge haul to kick start New York's rebuild.

Other relievers who could be made available before the deadline include Clippard, Hudson, Sean Doolittle, Joe Smith, Arodys Vizcaino, Will Smith, and Jeremy Jeffress, among others.