Mata (shoulder) is scheduled to throw 2-3 innings for Triple-A Worcester on Sunday, Jen McCaffrey of The Athletic reports. A decision on his activation will occur afterward.
Mata was pulled off his rehab assignment in late May for roughly three weeks, but he's appeared in six minor-league games since without any setbacks. Sunday's appearance could be Mata's final one, in which case the 25-year-old would join the Red Sox roster after the All-Star break.