Bullpen Report: September 16, 2014

-Not a great night for closers in Detroit. First, Glen Perkins coughed up a 2-0 lead by serving up a three-run tater to J.D. Martinez. Not to be outdone, of course, Detroit’s maligned closer Joe Nathan permitted a couple runs of his own (two hits and a walk) in giving the game right back to the Twinkies.

Perkins, who picked up a “W” for his three earned run effort, has scuffled to the tune of a 3.81 xFIP since the all-star break. That is not a horrendous mark, but it is a far cry from his elite rates earlier this season. The big problem stems from the nearly 10% fall in K% after the first half. Perkins’ velocity is down a bit in 2014 and looks to have sagged slightly over the last two months, so maybe there is smoke to the fire. He’s not in danger of losing his job for the rest of 2014, but may fall in the keeper rankings if he doesn’t show some serious improvement over the season’s last couple weeks.

There’s only so much that can be said about Nathan. His 4.13 xFIP is nearly a full run lower than his ERA, but 4.13 isn’t really a mark you want to see out of a shut-down guy on a contending team. After peaking mid-season, his fastball velocity is back to where it was at the beginning of the year, and his season average is well lower than either of his previous campaigns. With medicore velocity, declining strikeout rates, and a BB% that has broached double digits, age regression looks like it may have finally hit Nathan. Joakim Soria is healthy, owns a 2.24 SIERA, and racked up a save yesterday. Brad Ausmus has stuck with his guy all season, but in mid-September, it might finally time to call for the changing of the guard.

–Drew Storen helped Washington clinch the National League East with a clean save. Storen’s ERA is a shiny 1.25, but he has the triple-luck-fecta working with him. Suppressed BABIP (.255), high strand rate (92%) and lower than average HR/FB% (4%) are all helping keep his numbers in check. Both his xFIP and SIERA are north of 3.00, solid enough, but not elite. That said, his success has come at a critical time for the team, so look for them to continue riding him for now. He has pitched three days in a row, so look for Tyler Clippard or even Rafael Soriano tomorrow. A potential save opportunity could go a long way to telling us who will close down the stretch — if it’s Clippard, Soriano isn’t close. If it’s Soriano, well, the door is still open.

–Trevor Rosenthal blew his sixth save of the season tonight, walking a pair and giving up a hit. Command continues to be the righty’s Achilles’ heel — his 14 BB% is more than double that of his mark from last season. His pitch metrics (fastball velocity, swinging strikes, linear pitch weights) all paint the picture of a young guy with electric stuff, but as Carlos Marmol has shown us, you can have the best stuff in the world, it doesn’t matter if you don’t know where it’s going. Rosenthal’s job remains relatively secure, but like Perkins, his lost some of his keeper luster.

-Quick hits: Joaquin Benoit is due back on Friday. Snag him if he’s been dropped, although it’s unclear if he’ll just jump right into the ninth inning. Jonathan Papelbon was suspended for a week for “the crotch grab heard ’round the world.” You should have already owned Ken Giles, but if he’s still available, run, don’t walk, to get him.

Closer Grid:

[Green light, yellow light, red light: the colors represent the volatility of the bullpen order.]