Conference semifinal preview: No. 4 Celtics vs. No. 8 Sixers

KEY MATCHUP

Paul Pierce vs. Andre Iguodala. Pierce suffered a sprained MCL in his left knee last Sunday and is likely to be dealing with the injury throughout the playoffs. The Celtics need him to win his matchup with Iguodala, who is one of the best defenders in the league and Philadelphia's top all-around player coming off the decisive free throws he made with 2.2 seconds left Thursday to turn a Game 6 loss into a series upset. Iguodala played well against Luol Deng in the opening round, and now they need him to defend and attack another All-Star in Pierce.

X-FACTORS

Celtics: Kevin Garnett. His midseason move to center coincided with an improvement in his conditioning. Put them together and Garnett has become one of the best centers in the league in recent weeks. When he is aggressive -- as when he generated 28 points and 14 rebounds in the closeout win vs. Atlanta -- the Celtics are difficult to beat because he is so hard to cover around the basket, based on his ball-handling and shooting touch as well as his ability to create plays for others. The Celtics must play through him to establish the post presence they need to space for their other scorers.

Sixers: Evan Turner. Philadelphia went 4-1 after starting Turner in Game 2 against the Bulls. Based on his advantage of height over 6-foot-3 Avery Bradley, and his advantage of health over 36-year-old Ray Allen, the second-year guard will give the Sixers a boost if he's aggressive as a scorer and playmaker. But there are times when he struggles with his confidence, and the Celtics will try to attack him as they did during their blowout win at Boston in April.

BOTTOM LINE

If Rose hadn't been injured then Chicago would be facing Boston in this round. But don't disrespect the Sixers, who turned their season around in the last two weeks. The Celtics will win if healthy, though health cannot be assured for an elderly roster in this crazily truncated season. Celtics in six.