YES Network.com

David Robertson has been activated from the 15-day disabled list, and is available for Friday’s series opener against the Nationals in Washington.

Robertson went on the disabled list on May 16 with a strained left oblique, an injury he suffered while pitching the previous week. An All-Star in 2011, Robertson is 0-1 with a 2.51 ERA and one save in 15 games so far in 2012.

To make room for Robertson, the Yankees optioned pitcher David Phelps to Class-A Tampa. Phelps was 1-2 with a 2.94 ERA in 33 2/3 innings as a starter and long reliever this season, but has not pitched since throwing one-third of an inning on June 2 in Detroit.

According to YES Network’s Meredith Marakovits, Phelps has been sent to Tampa to get his arm stretched out.

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