BOSTON, SEPT. 24 -- Boston's Roger Clemens, sidelined with a sore right shoulder since Sept. 4, was given medical clearance to pitch on Friday against the Toronto Blue Jays.

"Roger feels he has pitched through more than this in the past," said Arthur Pappas, the Red Sox' doctor. "Roger wants to pitch and he feels he can pitch Friday night."

Clemens, 20-6 with a 1.98 earned run average, was stricken with severe tendinitis on Sept. 4 when he lasted 5 1/3 innings and had an eight-game winning streak ended by Oakland. Pappas, an orthopedic specialist, said Clemens had no structural damage within the shoulder and no rotator cuff problems.

After daily medication to reduce inflammation and fluid buildup, Clemens threw 80 pitches last Tuesday in the bullpen in Baltimore. He pronounced himself ready and was given the okay by Pappas on Thursday to return to action against the Yankees on Sunday. However, sensitivity in the back of the shoulder was noted Friday and his return was postponed. Clemens began warming up during Sunday's game but quit abruptly.

"He has knots in the back of his shoulder," Pappas said. "There's a twinge and he jumps if somebody touches it, but it's nothing that he hasn't had since July."

Pappas said that Clemens, a two-time Cy Young Award winner, would throw Tuesday and then get a final check Thursday before the Red Sox and Blue Jays meet in the opener of a three-game showdown Friday. Boston trails first-place Toronto by one game in the AL East.