It wasn't his absurd stat line of 45 points, 15 rebounds, and 5 assists. While it was definitely one of his best games, it's not like he hasn't done that sort of thing before.
It wasn't the way he lead the Heat to a blowout win. That's happened plenty of times.
It was his smile.
More accurately, it was the lack thereof.
Throughout the entire game, LeBron wasn't seen smiling a single time. Even when the game was out of reach late in the 4th quarter and LeBron was resting up on the bench, he covered his face with a towel any time he was talking, smiling or laughing.
A few days ago, in Game 1, LeBron was laughing in Kevin Garnett's face after a play.
Last night, he was a completely different person. No laughing, no smiling, all business.
Could this be a different chapter in LeBron's story? Was this the change that he needed to make to suddenly flip the switch and develop the killer instinct that he has seemed to lack throughout his career?
If so, the rest of the NBA better watch out.
An inspired, motivated, serious, and intense LeBron could do some serious damage.
He's clearly the most talented player in the NBA, perhaps the best in league history. If he can move past his struggles late in big games, whether perceived or actual, he could go down as the greatest player of all time.
LeBron didn't even NEED to play the 4th quarter last night, since his heroics led the Heat to such an insurmountable lead that it didn't even matter.
When he plays like he did last night, it's special to watch, and there might not be anyone in the league who can stop him.
Unfortunately, in Boston, fans didn't exactly appreciate it as much as they might down in Miami, if LeBron duplicates his effort in Game 7.
Is this a new LeBron? Or will he go back to wilting under pressure, possibly starting on Saturday night in Game 7? I guess we'll see.