Knicks coach Mike Woodson said if yesterday had been a Game 7, starting guard Pablo Prigioni likely would have suited up on his balky right ankle in the first-round playoff opener against the Celtics. Woodson said he believes Prigioni will be ready for Game 2 on Tuesday and for the Knicks, that is a good thing. That’s because Woodson started Chris Copeland at the wing, and he appeared hampered by a recent shoulder surgery and seemed a bit overwhelmed in his playoff debut. Copeland, recently a scoring beast, was scoreless in 12:46, going 0 for 3 in the Knicks’ 85-78 win. “He could be a little nervous,’’ Woodson said after Game 1 at the Garden. “I started him and started him in the second half. This is big-time basketball and when you never [have] done it, it can be an eye opener. He will be all right. [We will] watch tape tomorrow and we will get him comfortable.’’ Copeland said he could use the few days to rest his shoulder, which popped out in the regular-season finale. He wore supportive tape on his shoulder and a black T-shirt to cover it. “Could be better, but no excuses,’’ Copeland said of the sore left shoulder. “Rest will help.’’