There’s never any shortage of teams in need of pen arms. As the Cardinals’ early strike for Steve Cishek shows, even high-performing bullpens can often benefit from depth. Of course, we’ve also seen teams benefit in recent seasons by adding premium arms to their late-inning mix, as the Orioles did last year with Andrew Miller. But as that trade also demonstrates, the price for pen arms (in that case, Eduardo Rodriguez) is never higher than at the deadline.

Closers & Premium Set-Up Men

Jonathan Papelbon (Phillies), Francisco Rodriguez & Will Smith (Brewers), Aroldis Chapman (Reds), Craig Kimbrel & Joaquin Benoit (Padres), Koji Uehara & Junichi Tazawa (Red Sox), Tyler Clippard (Athletics), Joakim Soria (Tigers), Jim Johnson (Braves), Brad Ziegler (Diamondbacks), Brad Boxberger & Jake McGee (Rays)

At this point, Papelbon has largely silenced concerns about his ability to dominate with decreased velocity. At 34 years of age, he no longer racks up the double-digit K/9 tallies that he used to, and he’s outperformed his peripherals somewhat, but Papelbon still owns an outstanding 1.87 ERA with 8.7 K/9 against 2.0 BB/9 since the start of 2014. He’s playing on a $13MM salary this year and is close to triggering a vesting option for the same amount next season, but that doesn’t seem an outlandish commitment at this point and the Phils are reportedly willing to keep a good piece of the cost. The major limiting factor on Papelbon’s market is his 17-team no-trade list and perhaps his preference to go to a team that will use him in the ninth inning.

K-Rod may be the second most obvious closer trade piece. He’s cheaper than Papelbon, but not by as much as you might think (at least in the future). His backloaded deal includes $9.5MM in commitments after this season, including a $2MM buyout of a $6MM club option for 2017. Regardless, that’s a more appealing contract than that of the Phillies closer. And the 33-year-old has been every bit as excellent, with a 1.54 ERA and 10.0 K/9 against 2.3 BB/9 on the year.

Next up: the two best relievers in baseball, Chapman and Kimbrel. Both certainly could be had for the right price, but it remains to be seen how motivated their teams are to sell. Chapman has probably overtaken Kimbrel as the most dominant closer in the game, as he continues to compile truly remarkable strikeout numbers (16.0 per nine on the season) while Kimbrel has cooled down (relatively speaking) to the 13-per-nine range. Chapman is only controllable for one more season after the present, after earning just over $8MM this year through arbitration, while Kimbrel is guaranteed $25MM over the next two seasons and has a club option that could bring the total bill for his services to $37MM from 2016-18. You could debate their relative value at this point, but contenders would probably prefer to slot the Cincinnati lefty into their pen down the stretch.

Uehara lands in his own category, in large part because it’s unclear how inclined the Red Sox will be to consider moving him. The 40-year-old carries a 2.52 ERA this year, identical to his output last season, and continues to put up double-digit strikeouts while walking well under two batters per nine innings. He’s owed the same reasonable $9MM salary next year that he’s earning in 2015, but that may make Boston inclined to keep him.

Clippard and Soria are both working as closers, but look like set-up targets for contenders. Both are well-paid this year ($8.3MM and $7MM, respectively), and are pure rentals. It remains to be seen whether the latter will be marketed, but both would figure to draw fairly strong interest. His strikeouts are down and his walks are up (8.8 K/9 against 4.9 BB/9), causing ERA estimators to shudder, but Clippard still carries only a 2.79 ERA. Likewise, though Soria has shown increased velocity and carries a 2.93 ERA, he has fallen back to 7.7 K/9 (against 2.5 BB/9). Rumor has it that a Clippard trade could come as soon as today.

Johnson, too, could be viewed as a setup man, though he has a lengthy track record as a closer, including a pair of season in which he led the AL in saves. He’s back in the ninth inning following the Braves’ trade of Kimbrel and an injury to Jason Grilli. Johnson has a $1.6MM base salary, and his contract can max out at $2.5MM, which makes him one of the better buy-low pickups of the offseason and means that any team could afford his contract.

Benoit, Ziegler, and Tazawa all occupy similar positions as long-established late-inning arms on likely sellers who come with an additional season of control. Ziegler is serving as the D’backs closer, and Benoit has closed in the past, but all three profile as potential set-up additions for most teams. The first two are well compensated ($8MM and $5MM annual salaries, respectively), while Tazawa is a bargain at $2.25MM. As for 2016, it’s a similar story, as Benoit comes with a $8MM option, Ziegler’s option will cost $5.5MM, and Tazawa is controllable via arbitration. All three have typically stellar earned run averages, but Tazawa has the best peripherals this year, is by far the youngest of the group, and comes with the most appealing contract situation.

Smith and McGee represent two of the best late-inning lefties that could potentially be had at the deadline this year. The Brewers may well hold onto Smith, who is nearly certain to reach arbitration eligibility as a Super Two but will still be relatively cheap for some time given his lack of saves (or even holds). He’s put it all together this season, with a 1.75 ERA and 12.5 K/9 vs. 3.5 BB/9. Meanwhile, McGee has a somewhat lengthier track record and has been even better than Smith: he’s down to a 1.14 earned run average with a remarkable 10.7 K:BB ratio on the year. On the other hand, he already costs $3.55MM and will likely get nice raises each of the next two years in arbitration. That’s not as desirable as Smith’s status, but makes him quite a valuable piece — and one that is expensive by Tampa Bay’s standards.

Boxberger is an interesting trade chip for the Rays, who are reportedly considering a move involving one or more of their excellent arms. He has been plenty useful this year, though his run prevention and K:BB tallies are not a match for 2014 (when he posted a 2.37 ERA with 14.5 K/9 against 2.8 BB/9, along with a minuscule but BABIP-aided 4.7 hits per nine). There’s no urgency for Tampa Bay to move Boxberger, as he can be controlled through 2019 and will be eligible for arbitration only three times, but the club could be interested in selling high from an area of some surplus.

Right-Handed Middle Relief Targets

John Axford (Rockies), Jason Frasor & David Aardsma (Braves), Jonathan Broxton (Brewers), Kevin Jepsen (Rays), Edward Mujica & Ryan Cook (Athletics), Fernando Rodney, Mark Lowe & Tom Wilhelmsen (Mariners), Shawn Kelley (Padres), Matt Albers (White Sox), Ryan Webb (Indians), Burke Badenhop & Ryan Mattheus (Reds), Jeanmar Gomez (Phillies), Addison Reed (Diamondbacks)

Axford is a former closer that signed a fairly meager deal as a free agent over the winter, only to find himself back in the 9th inning due to injuries. He’s put up solid results, but ERA estimators value him more as solid-average than a late-inning stud, and contending teams likely will as well. That being said, his affordable contract and good recent work make him an appealing trade targets.

Otherwise, this group includes a wide array of potentially interesting players, ranging from struggling and expensive power arms (Broxton, Rodney, Reed) to affordable middle relievers with good recent numbers (Jepsen, Lowe, Gomez), with a wide variety of options in between.

Left-Handed Middle Relief Targets

Mike Dunn (Marlins), Oliver Perez (Diamondbacks), Marc Rzepczynski (Indians), Zach Duke (White Sox), Fernando Abad & Eric O’Flaherty (Athletics), Neal Cotts (Brewers), Manny Parra (Reds), Joe Beimel (Mariners)