SAN ANTONIO -- Defense carried San Antonio to the second-best record in the NBA this season but it's likely to be the Spurs' ability to get the most out of their offensive opportunities that will be the key for a push for a sixth championship since 1999.

Kawhi Leonard scored 20 points and LaMarcus Aldridge added 17 points as the San Antonio Spurs dominated the middle two quarters and romped past the Memphis Grizzlies 106-74 Sunday in Game 1 of the two teams' Western Conference quarterfinal playoff series.

San Antonio outscored the Grizzlies 24-6 over the final 8:04 of the third period, turning a contentious game into a runaway, and led 81-51 with a quarter to play. The fourth quarter was left to mostly the reserves, with Game 2 in the series to be played Tuesday in San Antonio with 8:30 p.m. CDT tipoff.

"It just takes a little while," said the Spurs' Tim Duncan, who had seven points and 11 rebounds. "Once we got it going, then some shots started falling. That's when we were able to extend the lead. Defensively, we were pretty solid the whole way through."

Tony Parker and Patty Mills scored 15 points each for the Spurs and Kevin Martin added 10 points, all in the fourth quarter. San Antonio hit on 42 of its 81 shots (52 percent), outrebounded the Grizzlies 44-35 and had nine blocked shots to Memphis' three.

Vince Carter led the Grizzlies with 16 points while Lance Stephenson hit for 14 points, all but two in the second half. Memphis, which has now lost all five games it played against the Spurs this season, was held to a season low in points, shot just 39 percent and went to the free-throw line only six times.

"Defense is the focus of our program and I thought in the second half we did that pretty good," Spurs coach Gregg Popovich said. "Our offense really bogged down in the first half -- we didn't move the ball and it was a lot of one on one.

"Against the Grizzlies, who are tough, physical and aggressive, the ball has to move other than dribble," Popovich added. "It's got to be passed and people have to move."

Both teams played a ragged first quarter as there were nearly as many bodies pushed to the floor as baskets made while each squad tried to establish a physical presence. The Spurs led 22-13 after 12 minutes of play despite shooting just 35 percent from the floor. Memphis hit on just 5 of its 22 field-goal attempts with the ageless Carter, making just his fourth start of the season, scoring the Grizzlies' first seven points.

Two baskets by Carter cut the Spurs' lead to 26-22 four minutes into the second quarter and gave the Grizzlies some momentum. But a Leonard steal and dunk followed by another dunk by Leonard off an assist by Mills on the ensuing possession propelled San Antonio on a 7-2 run and created some breathing room at 33-24.

Parker reeled off five straight points on back-to-back drives and a free throw in the final minute of the quarter to push the Spurs' lead to 48-37 at halftime. Aldridge had 13 points in the half and Leonard added 12 for the Spurs while Carter led the Grizzlies with 11 points in 12 minutes of court time.

"When you are turning the ball over and not getting shots, a five-point lead can turn into a 20-point lead in the blink of an eye," Carter said. "That's what happened tonight, and it rattled us a little bit. San Antonio takes pride in the way they close out quarters -- you are aware of what they are going to try to do when you play against them -- and that was the difference."

The Spurs rolled out to a 61-45 lead five minutes into the third quarter behind Duncan, who roared through the lane for a left-handed finger roll and then took the ball away from Zach Randolph at the defensive end, starting a fast break that resulted in a driving layup for Parker.

Duncan's play on both ends of the floor seemed to lift the Spurs, who found another gear over the second half of the third quarter and kept their foot on the accelerator.

"We have got to close quarters better," Memphis coach David Joerger said. "San Antonio went 10-2 at the end of the first quarter, 9-0 at the end of the second and 24-6 at the end of the third to go up 30 (points). San Antonio executed well offensively and our lack of offensive execution hurt our defense. We get mixed up, jumbled up and don't get back very well in transition. Those are things hopefully we will get better at."

NOTES: With a final record of 67-15, the Spurs produced their most wins in a season for the franchise, passing the 2005-06 Spurs, who finished 63-19. ... San Antonio is just the 12th team in NBA history to win at least 67 games in a regular season and tied for the seventh-best season ever. ... The Spurs finished the 2015-16 campaign with the second-best overall record in the NBA and a franchise-best 40-1 at home. ... Since 1997 the Spurs have recorded 19 straight winning seasons and compiled a 1,072-438 record to date, giving them a winning percentage of .710, which is the highest of any team in the four major professional sports during that time period. ... The Grizzlies have had six consecutive winning seasons -- only San Antonio and Oklahoma City (7) have longer streaks in the NBA. ... Memphis saw 28 different players log regular season minutes this season, the NBA record for most individual players in a single season. ... The Grizzlies became the first team in NBA history to make the Playoffs while playing 24 or more different players in a season.