The Spurs -- the NBA's top defensive team at 88.2 points per game -- held Atlanta to 25 points in the first half and romped to a 103-78 victory over the Hawks on Saturday night.
Forward Kawhi Leonard scored 22 points to lead San Antonio in scoring for the 15th time. Guard Manu Ginobili added 17 points off the bench as the Spurs led by as many as 28 points in the third quarter.
"It was one of those NBA nights. We had a good night and they had a poor night," Popovich said. "It happens now and then with good teams. We've had our games where we've basically laid an egg and the other team played well on top of it."
It is rare when San Antonio plays poorly, though.
The victory was the 17th in the past 20 games for the Spurs, who have the league's second-best record at 20-5.
"They're a good team. They've done this defensively to a lot of opponents this year," said Budenholzer, a former San Antonio assistant.
Leonard added eight rebounds, four assists and five steals to his point total and the Spurs won easily despite 23 turnovers.
The Hawks' final output was their lowest of the season, falling below what they had done in a 108-88 loss at San Antonio on Nov. 28.
It was the second half of a back-to-back for the Spurs, who arrived in Atlanta from San Antonio early in the morning.
The Spurs, though, hardly looked sleep deprived.
"It's hard to keep teams under 80, especially on the road," Ginobili said. "For three of the quarters, we were incredible. It was as good as it gets."
Forward Paul Millsap was the only member of the Hawks to get going offensively, scoring 22 points on 9-for-13 shooting from the floor.
"Tony's been wonderful at playing both ends of the court," Popovich said. "He set the tone for us defensively."
The Spurs led 47-25 at halftime despite 12 turnovers as the Hawks shot just 24.3 percent and had 12 less points than in their previous worst offensive half.
The Hawks' 12 points in the second quarter matched their low set in the same period during the loss at San Antonio and they missed 11 shots from point-blank range in the first half.
"We've got to finish better in the paint," Budenholzer said. "We've got to make more of our shots close to the basket."
Atlanta made just 3 of its first 17 shots and had to score the final four points of the first quarter to get within 22-13.
Leonard had 11 points and Ginobili added 10 in the first half. The Spurs were 4 of 6 from behind the 3-point arc while the Hawks were 1 of 9.
The Hawks finally got going offensively in the third quarter, more than matching their first-half point total as Millsap scored 17 points. The Spurs, though, still outscored Atlanta 32-30 for a 79-55 lead going into the final period.
NOTES: Hawks F Mike Scott (left knee contusion) missed his third straight game. "We keep hoping and thinking that he will be ready, but he's just not really there," coach Mike Budenholzer said. "I think it's kind of a day-to-day thing." Scott had an MRI exam, which Budenholzer said was "clean." ... It was the second of back-to-back games for the Spurs, who defeated the Los Angeles Lakers 109-87 on Friday in San Antonio. ... PG Tony Parker was rested for that game and G Manu Ginobili played just five minutes. ... G Ray McCallum, who started in place of Parker against the Lakers, was inactive versus the Hawks. ... The Spurs, 12-0 at home, host Utah on Monday to begin a stretch of four straight games in San Antonio. ... The game with the Spurs was the opener of a three-game homestand for the Hawks, who play Miami on Monday.