The possibility of the Yankees and Mets competing for a big-name pitcher always puts sizzle into a free-agent chase, but it remains to be seen how deep the two teams get into discussions over rehabbing righty Mark Prior, the ex-Cub. Both have expressed "preliminary interest" in Prior, John Boggs, the pitcher's agent, said yesterday. "But it hasn't been anything more than that. Next week will probably be pretty busy." Boggs says 11 teams have expressed interest in his client, who likely will be ready to pitch in the majors by the end of May. Prior, whose promising career has been derailed by injuries, was non-tendered by Chicago last week. Prior had arthroscopic surgery last season on his shoulder in which noted orthopedist Dr. James Andrews did some repair work to his rotator cuff and labrum. "He's playing catch right now and Dr. Andrews and his physical therapist feel like he's progressing nicely," Boggs said. "Mark is a guy who has no problem working hard. Barring anything unforeseen, he's going to be just fine. If we don't rush him, he could be very successful."