Kawhi Leonard made his long-awaited return from injury but could not stop San Antonio from an upset defeat in Dallas on Tuesday as LeBron James led the Cleveland Cavaliers to a ninth straight win.

Leonard, who missed the first 27 games of the season due to a thigh muscle injury, made an impressive cameo in his 15 minutes on court, scoring 13 points and pulling down six rebounds.

But when Leonard exited as expected early in the third quarter soon after helping the Spurs into a 55-50 lead, the Mavericks came back into the contest to run out 95-89 winners at the American Airlines Center.

The defeat was a jolt for San Antonio, who fell to 19-9 for the season. The Mavs improved to 8-20, led by 17 points from Harrison Barnes.

In Cleveland meanwhile, the Cavaliers rained down a bombardment of three-pointers on the Atlanta Hawks to secure a 123-114 win.

Cleveland bagged a season-high 20 three-pointers during the game, with James scoring 25 points and tying a career-high 17 assists.

Kyle Korver had 19 points -- including six three-pointers -- while Kevin Love had 17 points and 12 rebounds. Jose Calderon had 14 points.

- Happy to help -

James was satisfied with his tally of assists as much as his points total.

"For me to assist my teammates making shots has always been an enjoyment of mine ... my team-mates were excellent tonight," James said.

"We're in a good rhythm right now. We know what we want to run, we know where guys are going to be out on the floor, we kind of know how defenses have been playing us as of late and guys are moving and sharing the ball extremely well. When the ball is moving, energy is behind it and guys are in rhythm."

The Cavaliers improved to 20-8 and have now won 15 of their last 16 games to keep the pressure on Eastern Conference pace-setters Boston.

Cavs coach Tyronn Lue said the Hawks had struggled to contain James' passing threat.

"I think they do a lot of double-teaming and tilting with the bigs so that allows LeBron to just pick the guys apart," Lue said.

- 'Embarrassment' for Van Gundy -

Elsewhere Tuesday, Detroit Pistons coach Stan Van Gundy was left lamenting his team's "embarrassing" performance after a seventh straight defeat in a 103-84 rout by the Denver Nuggets.

"I've coached around 850 regular season games and playoffs and that's one of the worst ones I've ever had," Van Gundy said.

"We didn't do anything tonight. We didn't compete. That's on me as a coach. I've got to find the answers...that was an embarrassment tonight."

After a solid start to the season the Pistons are now 14-13 in the Eastern Conference.

Wilson Chandler scored 18 points for the Nuggets while Mason Plumlee had 10 points and a season-high 13 rebounds.

At Madison Square Garden, Kristaps Porzingis scored 37 points and had 11 rebounds as the New York Knicks overcame the Los Angeles Lakers 113-109 in overtime.

Enes Kanter had 14 points and 11 rebounds for New York while Knicks rookie Frank Ntilikina added a career-high 13 points.

The Lakers scoring was led by Kentavious Caldwell-Pope with 24 points while Lonzo Ball had 17 points, eight rebounds and six assists.

"You have to give them credit for making plays, but as a team you always look at what you can do better as a group, as an individual, and there is a lot tonight that we could have done better to give ourselves a better chance to win that game," Lakers coach Luke Walton said following the loss.

The Knicks improved to 14-13 with the win. The Lakers, who are 10-16 for the season.