Rafael Soriano, Joaquin Benoit, Dan Wheeler, Randy Choate, Grant Balfour and Chad Qualls all hit free agency last offseason, which created lots of uncertainty and a shortage of relievers for the low-budget Rays. Executive VP of Baseball Operations Andrew Friedman acknowledged from the beginning of the offseason that adding "a meaningful number of bullpen arms" was a top priority for the winter.
One fifth of the way through the season, the Rays' bullpen has been effective, while relievers such as Soriano and Benoit have struggled for their respective new clubs. Led by Kyle Farnsworth, Joel Peralta, Juan Cruz and Adam Russell, newcomers have accounted for 78% of the bullpen's innings this year. Now that Jake McGee is back in the minor leagues, Andy Sonnanstine is the lone member of Joe Maddon's 'pen that pitched for the 2010 team that won the AL East.
Low-risk, low-budget free agents (Farnsworth, Peralta and Cruz) the spoils of the Jason Bartlett trade (Russell, Cesar Ramos and Brandon Gomes) and a waiver claim (Rob Delaney) have combined with two holdovers (Sonnanstine and McGee) to post a 2.69 ERA through 87 innings of work. That bullpen ERA is good for third-best in baseball, as is the .582 OPS allowed by the 'pen so far. No bullpen has allowed fewer walks than the Rays (34) and only the Mariners (3) have allowed fewer homers than Tampa (4).
But there are indications that the Rays shouldn't expect these results from their new 'pen all season. Their relievers are last in the majors with 51 Ks and 5.3 K/9 and they're second-last in innings pitched (87) and BABIP (.215). Perhaps most telling of all is their 4.41 xFIP (also second-last in the majors), which is nearly two runs higher than their ERA.
Outstanding production isn't sustainable with some of the worst peripherals in the league, so it appears likely that the group's performance will drop off. But given the losses the Rays sustained last winter, it's impressive that Friedman's new collection of relievers has been this effective 20% of the way through another season.