The Mavericks Had One of the Biggest Postseason Upsets in 20 Years Last Night

The Mavericks beat the Thunder, and Raymond Felton had a meaningful playoff game in 2016. What a world.

The 2 vs. 7 matchup in the Western Conference wasn't supposed to be all that competitive. The Oklahoma City Thunder were the third-ranked team in our NBA Team Power Rankings this season with a nERD of 69.5 (our in-house metric meant to be predictive of the team's ultimate winning percentage). The Dallas Mavericks, on the other hand, were 15th with a nERD of 50.1.

The chasm between these squads is so great that our algorithms gave the Thunder a convincing 76.48% chance of winning the series, with the most likely scenario being that it would happen in just five games (25.24%).

Yes, that means that the Mavericks were likely to take at least one game from the Thunder, but no one expected that to be in Oklahoma City in Game 2 to even the series at 1-1.

And it wasn't even all that likely during the game, either. Even up until halfway through the fourth quarter, Oklahoma City was still a heavy favorite.

The Thunder opened up the game with 90.07% odds of winning, according to our algorithms. For the record, that's an insanely high probability at opening tip.

As you can see in the graph above, OKC's win probability never dipped below 75% once through the game's first three quarters. In fact, with 5:44 to go in the third, Kevin Durant hit a layup to make the score 58-50 in favor of the Thunder, pushing their chances of winning to 93.27% (which would prove to be their peak by game's end).

Even with only 6:17 left in the game's final frame, a Russell Westbrook jumper made the score 78-71 in favor of OKC and made them 90.98% favorites to win. Those single-digit margins may seem plenty surmountable on the surface, but the win probabilities remained high for the Thunder throughout because they are supposed to be that much better than the Mavericks.

And that's what makes the final score so unbelievable.

After a 10-3 Dallas run that evened the score at 81-81, the biggest win probability swing of the game happened with 29 seconds left, when Raymond Felton converted a layup to make the score 83-81 in favor of the Mavericks. That marked a 17.67% swing in favor of Dallas, putting their win probability at 76.36%. Wesley Matthews would then add a layup of his own with 14 seconds left, pushing the score to 85-81. The combination of that insurance bucket and the time that had run off the clock put Dallas' win probability all the way up to 95.00%.

The Mavericks had completed the improbable comeback and were a near lock to upset the Thunder at that point, but OKC did make it interesting.

Durant hit a three with 10 seconds left, making the score 85-84, then two quick fouls put Raymond Felton on the line. Felton, a guy who shot 84.7% from the line this season, went on to miss both free throws, setting the Thunder up for this sequence:

Durant's defensive rebound off of Felton's second missed free throw brought OKC's win probability roaring back to 35.78% with 7 seconds to go, a one-point deficit to overcome, and two of the best players in the known world on the floor in KD and Westbrook. Both those guys would then miss layups in traffic and Steven Adams' last-second tip-in was waved off for being on his fingertips for a approximately a millisecond too long.

Alas, the Mavericks closed out the game on a 14-6 run and ultimately won 85-84. Considering our algorithms had Dallas' win probability at a mere 9.93% at opening tip, this clearly qualifies as a massive upset. Just how massive? Well...

Of course, one game doesn't change the fact that the Thunder are a far better team than the Mavericks on paper and should still win this series. Let's be honest, how many more times is Kevin Durant going to shoot 7-for-33 from the field, while Raymond Felton puts up 21 points and 11 rebounds?

Homecourt advantage may now belong to the Mavericks, but OKC's odds of winning this series has only fallen from 76.48% going in to 67.76% after two games. The Thunder are still heavily favored, even if the most likely scenario has gone from their winning it in five games (25.24%) to seven (25.12%).

So, can the Thunder bounce back from an embarrassing loss and regain homecourt advantage? We'll find out on Thursday, when this series shifts to Dallas for Game 3.