Donning a big-league uniform for the first time, New York Mets right-hander Nolan McLean showed the poise of a veteran. The 24-year-old, the Club's top pitching prospect, fired 5.1 innings of scoreless ball, striking out eight Mariners batters, and pulled off a dazzling behind-the-back snag. "Surreal," remarked McLean on the debut. "I couldn't have dreamed it up any better."