The Islanders received a belated Christmas present yesterday when the club's medical staff determined that franchise goaltender Rick DiPietro has "no significant structural damage" in his sprained left knee. DiPietro underwent an MRI examination yesterday on Long Island after injuring himself in pregame warm-ups and pulling himself after the first period of the Islanders' 4-3 overtime win over Toronto on Wednesday. He did not accompany the Islanders to last night's game in Ottawa and is listed as day-to-day. Team spokesman Chris Botta said there's a chance DiPietro might return to the lineup as soon as tomorrow night against the Devils at Nassau Coliseum. "We're very convinced he's OK," Botta said.