James Harden hit three clutch shots in the final two minutes, Donovan Mitchell scored 35 points and the Cleveland Cavaliers beat Detroit 116-109 to cut the Pistons' lead to 2-1 in the NBA Eastern Conference semi-final series.

In Los Angeles, Oklahoma City continued to dominate the Lakers and now lead their Western Conference semi-final series 3-0 after a 131-108 victory.

For the Cavs, Harden bounced back from two mistake-marred performances to finish with 19 points and Jarrett Allen scored 18 for the Cavaliers, who will look to even the series when they host Game 4 on Monday night (Tuesday AEST).

Mitchell reached 2,000 career post-season points in his 73rd game, tied for third-fastest among active players and ninth in NBA history.

Detroit's Cade Cunningham had his second career post-season triple-double with 27 points, 10 rebounds and 10 assists, but also committed eight turnovers. Tobias Harris added 21 points.

Duncan Robinson's 3-pointer with 3:14 remaining tied it at 104 before Cleveland, who are unbeaten in five playoff home games, were able to seize control.

Max Strus intercepted an inbound pass by Cunningham at midcourt and made a breakaway layup with 2:28 left.

Harden, who drew plenty of criticism for turnovers in the clutch in the first two games, kept the Cavaliers in front with big shots. The 17-year veteran hit a 16-foot step-back jumper to extend the lead to 108-104. After a driving dunk by Cunningham, Harden made a floating 7-footer to put the lead back up to four.

Cunningham responded with a 3-pointer before Harden provided the decisive blow with 25 seconds remaining on a step-back 3-pointer while being guarded by Harris to make it 113-109.

Robinson was short on a 3-pointer after a timeout and Mitchell made three free throws down the stretch.

In LA, Ajay Mitchell had career playoff highs of 24 points and 10 assists, and Oklahoma City extended their unbeaten playoff run to the brink of another Western Conference finals.

Shai Gilgeous-Alexander had 23 points and nine assists for the Thunder, who coolly improved to 7-0 ? both in these playoffs overall, and in their seven games this season against LeBron James and the Lakers.

Oklahoma City are the NBA's sixth defending champion to start 7-0 in the following postseason after three wins over short-handed Los Angeles by a combined 59 points.

Game 3 was remarkably similar to Game 2 in many respects: The Lakers again had to fight desperately just to keep up with the champs into the third quarter, only for the Thunder to run away with their usual merciless efficiency when LA finally faltered.

Chet Holmgren had 18 points and nine rebounds for Oklahoma City, who outscored the Lakers 33-20 in the third quarter and weren't threatened at all down the stretch.

Game 4 is Monday night (Tuesday AEST) in Los Angeles.

James had 19 points, eight assists and six rebounds, while Austin Reaves had 17 points and nine assists. But both stars struggled from the field to a combined 12 for 32, and 21 points from Rui Hachimura weren't enough to keep LA in contention with the champs.