Tim Wakefield takes the mound for the Red Sox at age 44 years and 282 days. He breaks Deacon McGuire’s record as the oldest performer in Boston Red Sox history – McGuire was 44 years and 280 days old on August 24, 1908, his last game for the franchise.

On May 11, 2011 — Tim Wakefield takes the mound for the Red Sox at age 44 years and 282 days. He breaks Deacon McGuire’s record as the oldest performer in Boston Red Sox history – McGuire was 44 years and 280 days old on August 24, 1908, his last game for the franchise.

Source:
Baseball Reference May 11