The Red Sox reinstated Garcia (elbow) from the 15-day injured list Saturday, Jen McCaffrey of The Athletic reports.
Garcia (elbow) will begin a rehab assignment with Triple-A Worcester on Tuesday, Christopher Smith of MassLive.com reports.
The Red Sox placed Garcia on the 15-day injured list Tuesday with right elbow inflammation, Chris Cotillo of MassLive.com reports.
The Red Sox acquired Garcia from the Angels on Tuesday for an unspecified return, Jon Heyman of the New York Post reports.
Garcia earned a save against Oakland on Sunday, retiring all three batters he faced in the ninth inning.
Angels manager Ron Washington said Sunday that Garcia will take over at the club's primary closer, Sam Blum of The Athletic reports.
Garcia (5-1) earned the win over Seattle on Monday, allowing one hit and striking out two batters over one scoreless inning in relief.
Garcia earned the save over the Marlins on Tuesday after allowing one run on one hit and a walk in the ninth inning. He struck out a batter as well.
Garcia was charged with a blown save as a result of giving up one run on two hits and a walk against St. Louis on Friday. His only out came via a strikeout.
Garcia was credited with a hold Sunday against the Giants despite giving up two runs on one hit and two walks over one-third of an inning.