The Texas Rangers have signed relievers Diego Castillo and Reid Birlingmair and outfielder Michael Reed to minor league contracts, per the MLB.com transaction page, which indicates that the three were all signed on December 18.
Castillo is the most notable addition. A righthander listed at 6’3”, 268 lbs., Castillo has spent at least parts of the last six seasons in the majors with the Tampa Bay Rays and the Seattle Mariners. He was a solid if unspectacular middle reliever for most of that stretch, putting up a 3.