Boston's key to comeback is Shaq

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The key to slowing down the Heat and the surprising Joel Anthony is Shaquille O'Neal.

Shaquille O'Neal did not play much against the Heat in the regular season, appearing in just two of the four games for a combined 39 minutes. He has missed the first two games of the 2011 postseason series against Miami as well.

Head Coach Doc Rivers expects Shaq to play in Game 3 and though limited at this stage of his career, it could turn the tide in Boston's favor. During the regular season, Shaq's presence on the floor clearly improved the way that Boston played against Miami on both ends of the floor.

Celtics Improved Offensive Efficiency

With Shaq on the court in the regular season against the Heat, the Celtics averaged 121.1 points per 100 possessions, a stunning 26.2 points per 100 possessions improvement from when Shaq was off the court.

Boston shot a tremendous 54.1% from the field against Miami this season with Shaq on the court. That fell to 45.5% with Shaq off the court.

Some of the individual Celtics that saw the biggest differences were Rajon Rondo, who shot 34.5% from the field with Shaq off the court and 50% with Shaq on the court, and Ray Allen, who shot 50% with Shaq off the court and 68.8% with Shaq on the court.

The Shaq Effect

Many of Shaq's teammates have enjoyed much more success in their offensive games when The Big Shamrock was on the court at the same time as them this season. The five current Boston players that played with him against Miami each saw a meaningful elevation in the team's offensive rating (points per 100 possessions).

Boston's passing is one element of this improvement as its percentage of assists on made field goals increased from 61.4% to 66.7% when Shaq was on the floor.

A more obvious result of Shaq's presence is Boston's rebounding, especially on the offensive end of the floor. The Celtics rebound percentage was 54.2% with Shaq on the court, compared to just 45.7% with Shaq off the court. Boston's offensive rebound percentage increased from 17.0% to 33.3% with Shaq on the court.

Limiting Miami Defensively

Miami's offense felt Shaq's impact as well. The Heat had a net offensive rating of +8.0 when Shaq was off the court. However, the Heat had a net rating of -28.3 when Shaq was on the court.

Miami's shots were about a foot-and-a-half closer when Shaq was out of the game. The average distance of a Miami field goal attempt with Shaq on the court was 15.1 feet. With Shaq off the court, the average distance of an attempt was 13.4 feet (a 1.7-foot difference).

Effectively, Shaq helped neutralize Joel Anthony. In the 15 minutes that Shaq and Anthony played head-to-head in the regular season, Anthony's plus/minus took a major hit (-17). That means the that the Celtics outscored the Heat by more than a point per minute with Shaq and Anthony on the court at the same time.

Considering that Anthony currently has the best plus/minus in the 2011 postseason at +91, including +20 in the conference semifinals against the Celtics, Shaq's ability to play becomes that much more significant.