HOUSTON -- Russell Westbrook tapped his heart a few times when asked about the key to the Houston Rockets' rallying from 25 points down in Monday's 109-107 win over the San Antonio Spurs, their largest deficit overcome to win in at least the past 20 seasons.

"Sometimes you've got to want it more than the other team," said Westbrook, who led the Rockets with 31 points. "It's that simple. Ain't no plays or no possessions, no shots that can change that."

Houston coach Mike D'Antoni would love to see that demeanor from his team for the whole game. He noted that the Rockets' poor defensive start continued a disturbing recent trend, as Houston has allowed an average of 30.1 points in the first quarter of their past six games, which have all been against sub-.500 foes.

The Rockets held the Spurs to 35 points on 26.7% shooting in the second half. That was a stark contrast to the first half, when San Antonio shot 57.4% from the floor, scoring 37 points in the first quarter and 35 in the second.

"We were flying around the second half," D'Antoni said. "If we'd have flown around the first half, it would have been a lot easier. But maybe we'll have that mentality where we start games this way and get to be who we really are. When we play hard, we're pretty good."

The Rockets' turnaround started in the final 90 seconds of the first half, when they trimmed six points off the Spurs' lead. NBA scoring leader James Harden, who misfired on two of his first 15 shots from the floor, hit shots on the Rockets' final two possessions of the second quarter, including a 3 at the buzzer, to give Houston a bit of momentum entering halftime.

Houston's win after trailing by 19 at halftime matched the third-largest halftime comeback in franchise history and tied the team's largest ever at home.

Harden scored 19 of his 28 points in the second half, but he certainly didn't think his scoring was the biggest difference in the Rockets' performance before and after the break.

"It was just our intensity defensively," Harden said. "They were getting a lot of easy baskets from the beginning of the game. Defensively, in that second half, we were just a complete-opposite team. We were the team that we needed to be from the beginning of the game and throughout the course of the season."

Spurs coach Gregg Popovich, whose postgame media session lasted all of a minute, said that in some ways "it's just like your worst nightmare" to build a big, early lead, because the game is going to turn. The Rockets were on the wrong end of that phenomenon earlier this month in San Antonio, when Houston blew a 22-point lead in a double-overtime loss the Rockets protested due to an officiating error on a Harden dunk that wasn't counted.

"I know that throughout the season, you're going to have games like this," said Westbrook, who scored 25 of his points in the first half to keep the Rockets remotely within striking distance. "It's going to be a moment where you're going to be able to pick -- are you going to stay with it and fight through adversity or put your head down and make a decision [to give in]? Tonight we did a good job of sticking with it."

According to ESPN Stats & Information research, the Rockets trailed by as many as 28 points in the third quarter against the Cleveland Cavaliers on Dec. 17, 1972, and came back to win 110-109.