Pitcher Dennis "Oil Can" Boyd, who returned to the Red Sox lineup after being on the disabled list for 22 days because of a blood clot in his right shoulder, has returned to Boston for medical tests, the team said.

Boyd, after an encouraging performance against the Mariners Friday night, left Seattle for Boston after Sunday's victory over the Mariners and was to be examined today by Dr. Arthur Pappas, team physician.Boyd, a 28-year-old right-hander experienced pain Sunday in the shoulder that put him on the disabled list from July 29 to Aug. 19. He had had a blood clot dissolved on Aug. 5 in an artery leading to his shoulder.