The Red Sox signed Mata (elbow/lat) to a minor-league contract Friday, Chris Cotillo of MassLive.com reports.
Boston non-tendered Mata on Friday after designating him for assignment Tuesday, but the 25-year-old right-hander will stick around with the Red Sox organization. He'll continue to work through his rehab program for right shoulder and elbow soreness, and if he's healthy, he'll have a chance to earn a spot on the Red Sox's major-league roster in spring training.