For three quarters, the Warriors' defense had been stifling. Their offense was in its classic free-flowing form. They built up a 21-point lead at one point and were up 19 heading into the fourth. But as soon as the final 12 minutes started ticking down, there was a complete momentum shift, and it led to the Warriors losing to Dallas 107-101.
Golden State's 19-point blown lead is the largest blown fourth-quarter lead in the NBA this season.
"We did not maintain our grit down the stretch," Warriors coach Steve Kerr said. "We just let our momentum get away from us ...We can't just say, 'Oh well, when Draymond [Green] and Andre [Iguodala] get back we will be better.' It doesn't matter who's out there. We've got to get better executing under pressure and maintaining competence.
"It's actually good to go through and feel it because this is what it feels like in the playoffs, when you're playing against a really good team."
The deciding stretch of the game started at the 9:44 mark of the fourth and extended until there was just about 1:30 left in the game. For those 8½ minutes, Dallas went on a 26-1 run -- the Warriors' lone point coming off an Andrew Wiggins free throw.
Kerr credits the Mavericks' push to Dallas going small and Spencer Dinwiddie catching fire, scoring 10 of his 24 points in the fourth.
"We tried a few different combinations to try to regain the momentum and we just couldn't find anything," he said. "When they went small, we didn't respond. We missed some open shots and they just seized the momentum."
"We played great defense for 36 minutes," Stephen Curry said. "We felt like we had the game under control. For whatever reason, our energy shifted when we missed a couple of shots, empty possessions. They come down and score, we start getting deflated. And for no reason."
Curry's correct: The Warriors' defense early was stifling, particularly that of Wiggins and Gary Payton II. In the first half, Wiggins held the Mavericks to 2-of-11 shooting and forced three turnovers as the primary defender. He and Payton kept Luka Doncic to just 1-of-8 shooting and four turnovers.
But, as Golden State's offense went south, so did its defense.
"We let our offense dictate our energy and our spirit in the game," Kevon Looney said. "We kind of folded when adversity hit."
Sunday's meltdown marks the second consecutive home game and the second game of their previous three in which the Warriors have given up a sizable fourth-quarter advantage, the other being against the Denver Nuggets on Feb. 16.
"We got to figure out how to maintain our energy when the shots aren't falling," Curry said. "Because, that's what it might be like in a playoff game ... So I'd like to say it was a good lesson to learn, even though it sucks to have to go through it."
Curry does believe there are lessons the Warriors can take away from their game against the Mavericks, as does Kerr, who highlighted effort and execution under pressure as the two main areas he wants to see addressed.
But, it won't happen on its own. And as Kerr said, Golden State is far beyond the point of depending on Green's and Iguodala's returns.
"We've got to bring an edge," Curry said. "Sustain that over 48 minutes and each game we'll have an opportunity to do that -- to turn it into a positive and try to build momentum, but it's not going to happen on its own just because Coach says it or because we want it to. We've got to do it."