A rookie closer. A bunch of minor league starting pitching prospects who never panned out. A few no-name relievers. Some kids out of the farm system.

This is what Joe Girardi has had at his disposal in the Yankees’ bullpen throughout the 2014 season. On paper that group does not seem like much. Heading into the season the pen was projected to be a major weak spot for the Bombers, but as of now, that is not the case. To the surprise of many, the pen has been strong, especially David Robertson, Shawn Kelley, Adam Warren and Dellin Betances.

When New York opened the season, its relief corps consisted of the four above plus Matt Thornton, David Phelps and Vidal Nuno. Since then Nuno and Phelps have joined the rotation and several relievers have come along while others have hit the disabled list.

As of May 30, the Yankees’ pen looks as such: Robertson, Warren, Betances, Thornton, Alfredo Aceves, Preston Claiborne and Matt Daley. Kelley is currently out with a back injury but has already begun rehabbing and is expected to rejoin the club soon.      

Again, there is not much notoriety here, but this pen has done an exceptional job, far better than anyone could have hoped for. According to Fan Graphs, the Yankees’ bullpen has an ERA of 3.74 in 170.2 innings pitched. They are allowing less than one HR/9 and have a K/9 ratio of 10.49, the best in baseball. Lastly, and perhaps most importantly, the pen has a WAR (Wins Above Replacement) of 2.8, second to only the Red Sox‘s pen (3.0).

As mentioned, several Yankees are standing apart from the rest.

Despite having the unenviable task of replacing the game’s greatest closer in history, Mariano Rivera, Robertson has been everything the Yankees could have hoped for thus far. He has converted 11 of 12 save opportunities, sporting a 2.20 ERA, and has 27 strikeouts in 16.1 innings.

Kelley, before going down, was doing rather well in his new role as the club’s setup man. In 16 games he is averaging just over one strikeout an inning and has a 3.52 ERA. He has also yet to allow a home run this season. At one point, when Robertson was on the DL, Kelley served as the team’s closer, recording four saves in five opportunities. He is expected to throw a bullpen session May 30.        

Warren, after making 90 career starts in the minors, has emerged as a top-notch reliever this year. With a 1.76 ERA in 30.2 innings of relief, Warren has limited opposing batters to a .225 average this season. He has also surrendered just one homer.

Nobody has stood out more the Betances. Another failed minor league starter, Betances has seen his velocity, accuracy and consistency improve coming out of the pen. With a fastball that can reach 100 mph and a devastating slurve, Betances has been able to blow hitters away, striking out 51 in 30.2 innings of work.

In comparison, Detroit Tigers ace Justin Verlander has 50 strikeouts in 71.1 innings. Those same hitters have a miniscule .143 batting average against Betances. Add a 1.47 ERA and it is safe to say Dealin’ Dellin has become the Yankees’ best relief pitcher.

For Girardi, it has been a challenge not to go to Robertson, Betances, Warren and when healthy, Kelley, on a daily basis. Robertson has come in for three four-out saves in the month of May alone, and Warren and Betances are tied for the most innings pitched out of the bullpen.

“There’s times you just have to give guys days off,” Girardi said earlier this week. “That’s all you have to do. I’m trying to do that.”

Warren said his manager has done a fine job of doing that so far.

“There are certain days where you’re like, I could pitch, but I’d rather not just because of the way your arm feels. Joe’s been great at that. He kind of reads it to see how we feel, and he’ll sort of take the decision out of our hands.”

Betances echoed that thought as well: “Joe told me, if you ever need a day or feel sore, (say something). I told him I feel great. He’s communicating with me, trying to give me days whenever he can.”

Regarding his new shutdown reliever, Girardi wants to be careful with his workload, saying, “We’re trying not to kill Betances.”

Girardi, in his use and development of this no-name, no-experience pen, has done a phenomenal job. Very few people thought there was any potential here, but Girardi has brought this bullpen past the point of potential. The majority of this pen has proven to be reliable, some even dominant, and that is now the expectation when the starting pitcher leaves the game.        

All stats were obtained via Baseball-Reference unless otherwise noted and are accurate as of May 30, 2014.

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