First, the All-Star point guard was a threat to get to the rim at any moment. Then, he added a mid-range game to keep defenders off-balance. Now, he's getting rid of the bad decisions that were the biggest weakness left in his game.
"Personally, I think he's the most athletic guy in the NBA for what he does and how he does it and how quick he does it."
After surviving the constant threat of triple-doubles from Rajon Rondo during the Eastern Conference finals, the Heat will have their hands full at the point once again.
The series starts with Game 1 in Oklahoma City on Tuesday night.
Westbrook brings his own triple threat of blazing speed, defensive intensity and often-deadly shooting. And if he can keep taking care of the ball, there's one less way to stop him.
Westbrook's 1,097 turnovers during his four-year career are the most of any NBA player during that span - a stat skewed slightly by the fact that he hasn't missed any of the 312 games played. Westbrook's per-game turnover average was among the 10 worst in the league all four of his seasons, and he was worst of all last season with 3.9 per outing.
But during the playoffs, he's committing about one-third less turnovers while slightly upping his assist totals.
"You see where we're at. We're in the finals because of Russell, because of our leader, our point guard," Thunder teammate James Harden said. "He's done a phenomenal job of really controlling the ball, making the extra pass, and then when his shot is there or when his lane is there, he's taking it to them.
"He's done a great job of that and hopefully he can continue to do it."
Miami just got through dealing with Rondo, who averaged 20.9 points, 11.3 assists and 6.9 rebounds in the East finals. The Heat were able to win despite a 44-point, 10-assist, eight-rebound effort from Rondo in Game 2 and his Game 7 triple-double.
It was the sixth triple-double ever in a Game 7 and the first since - who else? - Westbrook did it in last year's West semifinals against Memphis. The others to accomplish the feat were Larry Bird, Jerry West, James Worthy and Scottie Pippen.
"My job is to make sure we win," said Westbrook, who's averaging 21.7 points, 5.6 assists and 2.3 turnovers in the playoffs. "So, whatever it is that I need to do to make sure we get the win, that's what I'm going to do."
Wade expects he'll get a turn guarding Westbrook and he thinks Miami will have to use a series of different defensive looks. It won't be all on Heat starting point guard Mario Chalmers, just as he wasn't the only one dealing with Rondo in the Boston series.
"It's been fun. To be the best, you've got to go against the best. So, I'm striving to be one of the elite point guards in the league," Chalmers said. "To have my name mentioned with them, I've got to go against these guys."
Chalmers said defending Westbrook starts in slowing down the Thunder's transition game and keeping him out of the paint.
"We'd rather have him shooting pull-ups than have him getting all the way to the rim," Chalmers said. "You've got to pick and choose your battles."
Westbrook averaged 20.5 points while Oklahoma City split two regular-season meetings with the Heat, but was relatively inefficient. He made only 13 of 42 shots and had eight assists against eight turnovers.
Coach Scott Brooks said understanding Westbrook's impact goes beyond those numbers, though.
"A lot of times you focus on the wrong things, at least some people do," he said. "But I really believe that what he does, he brings great energy, he brings great passion, he brings enthusiasm to the practice floor, and it carries over on how we play as a team on the game floor."
Westbrook's turnaround has led to an even more dramatic improvement for his team during the postseason. After committing the most turnovers in the league during the regular season, Oklahoma City has the second-fewest in the playoffs and best turnover margin of any team.
"A lot of times, his initial play in a possession dictates whether we're going to have a good possession or not," forward Nick Collison said. "He's always going to be a competitor, he's always going to play hard, he's always going to battle against the other team and the guy he's playing against.
"But the decision-making now, he's getting so much better at, and that's really helping us."