At his height, there’s no way Isaiah Thomas should be able to score as well as he does. The odds are certainly stacked against him considering only two players in NBA history under 6-feet have ever averaged 25 or more points in a season: Calvin Murphy for the Rockets in 1977-78 (25.6 points) and Michael Adams for the Nuggets in 1990-91 (26.5 points). Thomas is currently averaging more points than both them (27.8 per game) on a much greater effective field goal percentage and true shooting percentage.

Other than saying there isn’t much he can’t do on the court, it’s hard to pinpoint what exactly makes Thomas such a difficult matchup for defenders. He’s incredibly quick with the ball in his hands and he’s one of the craftiest finishers in the NBA. He’s also a knockdown shooter when it comes to both pull-ups and spot-ups. When you put those together, he’s someone teams can’t back off of or press up too closely because he’ll basically take whatever he’s given.

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Elevating Thomas to the next level is he knows how to use that dual threat to his advantage by making defenders think he’s going to do one thing before doing another with nifty changes in speed. His half-spin — or fake spin, as some prefer to call it — in particular might be the most underrated move in the NBA.

The move is what it sounds like: Thomas fools his defender into thinking he’s going to spin 180 degrees to attack in the opposite direction, only to stop halfway through and continue going in the direction he was initially heading. While simple, the possession below involving Wizards guard Tomas Satoransky is perhaps the clearest example of how effective it can be in a one-on-one situation.

Players rarely attack a set defense immediately following a dead ball because it’s hard to score against five stationary defenders who all have their eyes on the ball handler. That’s why the Celtics keep the Wizards engaged on the weak side — notice how Marcin Gortat and Otto Porter Jr. turn their backs to Thomas — by making it look like the play is for Avery Bradley to run off a pair of screens for a jump shot on the wing.

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From there, Thomas uses the half-spin to freeze Satoransky by baiting him into shifting his momentum forward. With Thomas’ quickness, which he maximizes by not actually planting his left foot on the floor and instead using it as a springboard, there’s absolutely no way Satoransky will be able to recover in time to prevent a layup.

Sometimes it doesn’t look like the defender bites much on the move, but the slightest hesitation can be the difference between someone playing good defense on Thomas and getting absolutely burned. Just watch how Rondae Hollis-Jefferson barely slows down in the following clip. While he sticks with Thomas rather well afterward, Thomas is so good at keeping a defender on his hip and using his body to create separation at the rim that he makes it look easy.

There are plenty more examples of Thomas using the half-spin to shred defenders in half-court sets. Here, Thomas breaks it out in a pick-and-roll with Tyler Zeller to fool Kyrie Irving and Tristan Thompson. Once again, pay attention to the timing of the move and how the defense reacts to it.

The problem for the defense is cutting Thomas off before he can get into the paint rarely works out well for them. The best pick-and-roll players know how to create space at the point of attack in order to put the big man in a better position to set a screen. It’s a skill which helped Kemba Walker, for example, become one of the best pick-and-roll scorers in the league. Therefore, defenders have to expend so much energy getting back in front of Thomas when he uses the half-spin that they’re more vulnerable to be screened if they’re "successful."

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Check out this video to better illustrate the point. When Thomas is cut off, he simply turns around to receive a down screen from Al Horford. Since Rodney Hood loses a significant amount of ground by trying to stay in front of Thomas, he can’t get out to Thomas at the 3-point line in time to disrupt his shot.

Thomas has a lot more tricks up his sleeve when he has an opportunity to break a defender down, but the half-spin is one of the most effective. For someone who is elite at scoring from underneath the basket, midrange and the perimeter, being able to change direction and speed at the drop of a dime means the defense can never get comfortable when he’s on the court.

That includes defenders who tower over him.