Garnett had been battling a nagging left foot injury for the last month or so, which forced him to miss eight straight games from the end of March to the beginning of April. Garnett played three games since returning from the injury on April 7 and averaged 23.7 minutes in those contests. He also sat out two games since the return, including the Celtics' regular season finale against the Toronto Raptors.
Boston needs Garnett at or close to full strength if they want to have a chance to upset New York, as the Celtics' defense is a completely different animal when he's on the floor. When Garnett is playing, the Celtics' defensive rating is an impressive 96.2, according to NBA.com. But when he's off the floor, that number skyrockets to 104.6. So the longer Garnett can stay on the floor in this series, the better for Boston.