Mark Messier would seem to be the best and natural choice to replace Don Maloney as the Rangers' assistant general manager, except Messier does not want the job. Not now anyway. Appearing as a guest of Mike and the Mad Dog on WFAN yesterday, Messier took his hat out of the ring for a job that opened this week, when Maloney was named GM of the Phoenix Coyotes. "I'd like at some point to get back into the game," Messier said from Anaheim, where he is working for Versus on the Stanley Cup Finals telecasts. "But at this particular point, I don't think I'm quite ready for it."