David Robertson was a key reliever for the Yankees in 2011. Reuters

Fresh off their blockbuster trade for right-handed phenom Michael Pineda, and the signing of veteran starter Hiroki Kuroda, the New York Yankees bolstered their bullpen by retaining two prominent set-up men, on Tuesday.

The Yankees avoided arbitration with relievers Joba Chamberlain and David Robertson by signing the two right handers to one-year, non-guaranteed, contracts.

Robertson has proven to be one of the better relievers in the American League. The 26-year-old had an earned-run average of 1.08 in 66 and two-third innings last season.

Chamberlain was sidelined for most of the 2011 season, but finished with a 2.83 ERA in 28 and two-third innings. In June, he underwent surgery for a strained right flexor muscle. In 2010, the 26-year-old had a 4.40 ERA in 71 and two-third innings