The Boston Celtics yesterday signed St. Johns point guard Omar Cook to a contract, although he will not play tonight against the Hawks nor will be he playing in the playoffs.  Paid $75,000, Cook?s will remain the property of the Celtics over the off season meaning that maybe Boston will get their first round pick overall.  Cook was considered a first round pick in last June?s draft but ended up going early in the second before being waived by the Denver Nuggets then by the Dallas Mavericks.

''He's a little more seasoned now, although he's still young at 20 years old,'' Celtics general manager Chris Wallace said yesterday. ''He's been around the block. He's ridden the buses in the developmental league. But he played well for Fayetteville and he is a kid who is very good in the open court. We thought he was worth a look.''

The Celtics placed forward Antoine Walker on the injured list to make way for Cook.