LeBron James' Cramps, Miami Heat's Response Reveals Fortitude Built on Last Year's FailuresThroughout the Oklahoma City Thunder's run to the NBA Finals, we have been reminded that we are watching a future champion grow before our eyes.

That indeed has been true, but the likely champion exhibiting its growth in the finals thus far has not been Kevin Durant and the Thunder, but the much-maligned Miami Heat.

Mario Chalmers did not bat an eye when LeBron James came up lame with a little more than five minutes remaining in Tuesday's Game 4. Dwyane Wade bore down again on defense, as he has throughout his offensively inconsistent postseason. Shane Battier stoically switched back onto Durant, who James had defended so effectively to that point.

With the way the Heat responded, their 104-98 victory was not surprising, even if James watched with a grimace from the bench as the final buzzer sounded.

A year ago, the Heat would not have had the fortitude to survive and even thrive with their best player missing three minutes, five seconds of the final 5:15 in a pivotal Finals game. Four times in the last five games last year against the Dallas Mavericks, the Heat were not even able to survive with their best player on the floor. Yet while the first-time finalist Thunder bumbled and stumbled down the stretch, just as the Heat did last year, the Heat acted as though they had been there before because they had been.

James was initially forced to the bench at the 5:15 mark after experiencing painful cramps in what appeared to be his right thigh, shortly after he hit a one-handed bank shot to give Miami a two-point lead. With James out, the Thunder took back the lead, which lasted until Bosh tied it up two possessions after James re-entered the game.

Following a miss by Russell Westbrook — one of only two shots Westbrook missed in the fourth quarter — James had his Willis Reed moment. In the first of a series of inexplicable crunchtime decisions by Oklahoma City, defender Thabo Sefolosha backed up two steps off James, who essentially could not walk. James almost certainly would have had to pass the ball if Sefolosha had crowded him, but given and extra few feet of space, James reared back and fired a 3-pointer to give the Heat a lead they would not relinquish.

James needed to exit the game less than two minutes later when the pain apparently became unbearable, and he watched the final 55 seconds from the floor in front of Miami's bench. Chalmers scored all five of the Heat's points after James departed and Wade delivered two steals and one huge block in the gut-wrenching fourth. But James' three silenced his legion of critics. There could be no argument, for instance, that the Heat closed this one out without James' help after he put his final mark on a 26-point, 12-assist, nine-rebound performance with that hobbling dagger.

The Heat were not without help from the other side. While James and Chalmers were busy pulling within one victory of their first championship, the Thunder looked every bit the part of young up-and-comers who are not ready to be titlists. Westbrook's sterling 17-point fourth quarter, part of a 25-point second half that saw him finish with 43 points and almost single-handedly put Oklahoma City in position to win, will inevitably be forgotten because of one miscalculation.

Westbrook had kissed a shot off the glass to pull the Thunder within three points, and Wade responded by missing a floater. Udonis Haslem and James Harden came out of the ensuing rebound scrum with simultaneous possession, leading to a jump ball and resetting Miami's shot clock to five seconds with 17 seconds to go in the game. Even if the Thunder lost the tip, the shot clock would start as soon as the ball was touched and the Heat would need to scramble to get off any shot, much less a quality one.

When the bouncing ball found Chalmers' hands, though, Westbrook fouled him, and it appeared to be intentional. The mistake was shockingly reminiscent of Game 3, when Harden committed a foul on James late in the shot clock while the Oklahoma City bench adamantly called for the Thunder not to foul.

Chalmers hit both free throws to give Miami a five-point lead with 13 seconds left to ice the Heat's win.

No matter how often teams review such situations in practice, there is no replacement for actually living through said situations. What the Heat were criticized for so roundly last year as a lack of guts now appears merely to have been a lack of experience. What may look like a series of boneheaded errors by the Thunder derive from the same place — although those errors were truly as boneheaded as can be, that is for sure.

The Heat played down James' injury after Game 4, with coach Erik Spoelstra dismissing any notion of a serious, long-term malady and Wade laughing, "He'll be all right."

Wade could have been talking about any member of his team. When the game gets tight and the clock gets low, the Heat no longer look uncertain or afraid of what comes next. They seem poised and confident that whatever happens, with James or without him, they'll be all right.

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