James Harden scored 28 points to help the Los Angeles Clippers overcome Kawhi Leonard's absence and come through with a 109-97 victory over the cold-shooting Dallas Mavericks in Sunday's Game 1 of a Western Conference quarter-finals series.

Harden and Ivica Zubac each stepped up with the fourth-seeded Clippers missing Leonard due to inflammation in his surgically repaired right knee. Zubac set a play-off career high with 20 points while grabbing 15 rebounds, while Harden went 6 of 11 from 3-point range in addition to dishing out eight assists.

Los Angeles also used a strong defensive effort to gain the upper hand in this best-of-seven series. Fifth-seeded Dallas shot just 38.8 per cent for the game and especially struggled in the

second quarter, missing 19 of 21 field goal attempts while being outscored by a 22-8 margin for the period.

The Clippers took a commanding 56-30 half-time lead behind their dominant second quarter, as they held the Mavericks' star duo of Luka Dončić and Kyrie Irving to a combined 17 points on 5-of-19 shooting over the first two periods.

Irving regrouped in the second half to finish with 31 points. Doncic compiled 33 points, 13 rebounds and six assists, but the NBA MVP finalist ended 11 of 26 from the field and 4 of 12 from 3-point range.

Paul George added 22 points for Los Angeles, which shot 50 per cent (18 of 36) from 3-point range compared to 30.3 per cent for Dallas.

Game 2 will take place Tuesday in Los Angeles.

 Lillard carries Bucks past Pacers with Antetokounmpo still unavailable

The Milwaukee Bucks were also able to withstand the loss of a superstar in their series opener, as Damian Lillard set a franchise play-off record with 35 first-half points to lead the way in a 109-94 Game 1 win over the Indiana Pacers.

Lillard didn't score after half-time, though his prolific performance through two quarters was more than enough to give Milwaukee, the Eastern Conference's No. 3 seed, a 1-0 series lead despite Giannis Antetokounmpo still recovering from a strained left calf he sustained late in the regular season.

The two-time league MVP's absence wasn't a major factor thanks in large part to Lillard, who tallied 19 first-quarter points as the Bucks opened up a 30-21 lead after 12 minutes before breaking the game open in the second.

Lillard put up 16 more points in the second quarter as Milwaukee outscored the Pacers by a 39-21 margin for the period to build a sizeable 69-42 lead at the break.

Khris Middleton scored 15 of his 23 points after half-time to keep the Bucks ahead by double digits the entire second half.

Middleton added 10 rebounds and Bobby Portis also notched a double-double with 15 points and 11 boards.

Sixth-seeded Indiana received 36 points and 13 rebounds from Pascal Siakam, but the Pacers shot just 20.5 per cent (8 of 39) from 3-point range and never led after the game's initial stages.

Indiana will attempt to bounce back in Tuesday's Game 2, which will again be held in Milwaukee.

 Celtics cruise past Butler-less Heat in series opener

The Miami Heat, on the other hand, had a far more difficult time dealing with two key players missing as the defending Eastern Conference champions were dealt a 114-94 loss by the top-seeded Boston Celtics in Game 1 of the teams' quarter-finals series.

Jayson Tatum registered his first career play-off triple-double with 23 points, 10 rebounds and 10 assists to lead Boston, which lost in seven games to Miami in last season's East finals. 

Derrick White added 20 points and Kristaps Porzingis had 18 as Boston never trailed against an eighth-seeded Miami team playing without six-time All-Star Jimmy Butler and starting guard Terry Rozier.

Butler is likely out for the series after injuring his right knee during the play-in round, while Rozier has missed the Heat's last seven games with a neck strain.

Boston set the tone right from the start by opening the game on a 17-2 run. Miami later countered with a 9-0 spurt to cut its deficit to 26-23 early in the second quarter, but that was as close as the Heat would get the rest of the day.

The Celtics answered with an 11-2 run to go back ahead by double digits, and their lead swelled to 60-45 at half-time as Tatum scored 10 points in the second quarter and reserve Sam Hauser drained four 3-pointers during the period.

Boston kept pouring it on after the break, as it built a 91-59 advantage after three quarters.

Bam Adebayo led Miami with 24 points, while Delon Wright hit all five of his 3-point attempts in a 17-point effort off the bench.

The series resumes Wednesday in Boston.

 Top-seeded Thunder hold off Pelicans in series opener

Shai Gilgeous-Alexander scored 28 points and converted a tie-breaking three-point play with 32.5 seconds left to play as the top-seeded Oklahoma City Thunder held on for a 94-92 win over the New Orleans Pelicans in the opener of another Western Conference quarter-final series.

Playing their first post-season game since 2020, the Thunder prevailed despite eighth-seeded New Orleans rallying from a 10-point deficit early in the fourth quarter to tie the contest with under four minutes remaining.

The Pelicans, who were without star forward Zion Williamson due to a left hamstring strain, had a chance to pull out the victory but CJ McCollum missed a 3-point try shortly before the buzzer.

Oklahoma City appeared to have seized control after ending the third quarter on a 9-2 run to take a 74-68 lead entering the fourth. The margin later grew when Chet Holmgren buried a 3-pointer with 10:25 remaining that gave the Thunder an 82-72 advantage.

New Orleans answered with a 9-2 spurt to get back in it and later pulled even when Herb Jones' 3-pointer created an 88-88 tie with 3:58 left.

The game remained deadlocked at 90-90 until Gilgeous-Alexander was fouled while knocking down a short floater with 32.5 seconds on the clock. The NBA MVP finalist made the ensuing free throw for a three-point Oklahoma City edge.

McCollum, who finished with 20 points, hit a jumper on the subsequent possession, and the Thunder gave New Orleans a chance at the lead when Holmgren made just 1 of 2 free throws after being fouled with 14 seconds left.

The Pelicans got the ball to McCollum with time winding down, but the veteran misfired on a contested 30-foot shot as Oklahoma City hung on.

Jalen Williams added 19 points for the Thunder, who will host Game 2 on Wednesday, while Holmgren posted 15 points and 11 rebounds.

New Orleans was led by Trey Murphy's 21 points, while Jonas Valanciunas pulled down 20 rebounds to go along with 13 points.