Red Sox pitcher Jonathan Aro (2-1) surrendered a hit, an earned run and a walk over two-plus innings in a 6-5, extra-inning defeat to the Orioles on Tuesday.
Aro made his first appearance after his most recent call-up from Triple-A Pawtucket, and the rookie reliever allowed the first two Orioles to reach base in the 13th, setting the stage for Chris Davis' game-winning hit.
The Red Sox figure to retain Aro on the major league roster for the remainder of the 2015 season in an effort to provide him with experience and to give some relief to their tired bullpen.