The Lakers (14-9) are allowing an average of 111 points per game, but they've given up fewer in seven of the past eight games while going 6-2.
"Defensively we've been in tune," Lakers forward LeBron James told reporters after practice Tuesday. "This is what we preach around here every day, so it has to be sustainable. It needs to become the norm, and it is the norm for us now."
San Antonio (11-13) is coming off a 139-105 loss at the Utah Jazz on Tuesday night, spoiling its chance to win two in a row for the first time in a month.
DeMar DeRozan and LaMarcus Aldridge, the top two scorers for San Antonio, were replaced with 8:07 left in the third quarter and didn't return. They'll try to keep San Antonio from dropping three games under .500 for the first time this season.
DeRozan, a Los Angeles-area native, is averaging 31 points, 10 rebounds and 11 assists in two games against the Lakers this season, both wins. The Lakers did not have third-leading scorer Brandon Ingram in either game, however. Ingram was suspended four games for his involvement in a fight against the visiting Houston Rockets on Oct. 20.
The Lakers and Spurs met two days later at Staples Center and San Antonio won 143-142 in overtime. Los Angeles rallied from an eight-point deficit with just over a minute left in the fourth quarter, and the Spurs began erasing a six-point deficit with 51 seconds left in overtime.
Ingram was serving the final game of his suspension when Los Angeles traveled to San Antonio and lost 110-106 on Oct. 27.
San Antonio small forward Davis Bertans replaced Dante Cunningham in the starting lineup the past two games, and the 6-10 third-year player from Latvia has combined to shoot 4-for-7 for 3-point range in the two starts and score 18 points.
Spurs coach Gregg Popovich told reporters before the game that he likes how Bertans' size and 3-point shooting ability can open gaps in the floor for DeRozan and Aldridge, who do most of their scoring from inside the 3-point line.
"You have to have a spread floor these days," he said. "It's the way it is."
Bertans had started two other games this season, including the win against the Lakers on Oct. 27.
The Lakers still have plenty of areas they're looking to improve. One is their turnover rate. They're averaging the fourth-most turnovers in the league (15.7), and have committed at least 15 in six of the past seven games.
"We've just got to be more careful with the ball, that's all," James said. "Sometimes, you're going to have turnovers where you're actually trying to make the right play. Sometimes, you can make turnovers by being too unselfish, and then you have some of them that are just careless and unforced. It's a combination of a lot of things, but I love where we're at."