One of the Mavericks' X-factors in their NBA Finals matchup with the Heat is Caron Butler, who has been out with a knee injury since New Year's Day. ESPN Dallas reports that Butler hasn't ruled out coming back to play for Dallas in the NBA Finals.

Butler hasn't been cleared to practice, much less play — five months isn't quite enough for a torn patella tendon to fully heal — but if he's available for the Mavericks, it might be a significant boost to Dallas' chances. Butler played in both of the Mavericks' regular season matchups with the Heat, and scored 23 and 13 points in the two Dallas wins.

More importantly, with Butler assigned to guard LeBron James, the Heat superstar struggled: James averaged just 21 points per game in the two contests, and made a woeful 11 of 36 shots from the field as Butler's stingy defense and the Mavericks' zone schemes flummoxed him.

A still-injured Caron Butler in June 2011 might not be able to do as much against James with a knee injury limiting his mobility, and would likely be able to contribute even less on the offensive end if he is inserted into a system that has adapted without him in the second half of the season. But even approximating that defense for a short stretch might be the sort of thing that swings an NBA Finals game — and, subsequently, an NBA title.

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