Doncic shines as Mavs take lead in NBA semi series

Luka Doncic scored 31 points in a triple-double as the travelling Mavericks beat the Thunder 104-92 to take a 3-2 lead in their NBA Western Conference semi-final series.

Doncic, the league's leading scorer in the regular season, had struggled in the series against Oklahoma.

Playing through a sprained right knee and a sore left ankle, he averaged just 22 points on 39 per cent shooting through the first four games.

He made 12-of-22 field goals in Game 5 on Wednesday night (Thursday AEST) and had 11 assists and 10 rebounds for his sixth career playoff triple-double.

Derrick Jones Jr scored a playoff career-high 19 points and P.J. Washington Jr added 10 points and 10 rebounds for Dallas, who shot 52.6 per cent from the floor.

Australian Josh Green had two rebounds, three assists and five points from his 18 minutes of court-time for Dallas.

The No. 5-seeded Mavericks can advance to the Western Conference finals with a home win on Saturday.

Shai Gilgeous-Alexander scored 30 points for the top-seeded Thunder.

Oklahoma tried to jump-start their struggling offence by replacing Australian Josh Giddey with Isaiah Joe in the starting line-up. Giddey did not start for the first time in 229 combined regular-season and post-season games.

Dallas led by 15 in the second quarter and took a 54-44 edge into halftime.

Gilgeous-Alexander scored 14 points in the third quarter, but Dallas still led 79-67.

Dallas pushed their lead out to 18 points early in the fourth quarter before the Thunder surged. A three-pointer by Gilgeous-Alexander cut the deficit to 89-79 with just under seven minutes remaining and forced Dallas to call a timeout.

The Thunder never got closer than seven points the rest of the way.

In Boston, Jayson Tatum had 25 points and 10 rebounds as the Celtics beat the Cavaliers 113-98 to advance to the Eastern Conference finals for the third straight season.

Al Horford added 22 points, 15 rebounds and six of Boston's 19 three-pointers to post their third consecutive win and clinch the series 4-1.

The Celtics will now await the winners of the match-up between the Knicks and the Pacers. New York lead that series 3-2.

The Cavaliers played extremely short-handed without All-Star Donovan Mitchell (calf), centre Jarrett Allen (rib) and key reserve Caris LeVert (knee).

Cleveland stayed close through the first three quarters and pulled within 88-85 early in the fourth. Boston then went on a 13-2 run to take a 101-87 lead with 6:44 to play.

Evan Mobley scored a playoff career-high 33 points and had seven rebounds for Cleveland. Marcus Morris Sr had five three-pointers and finished with 25 points.

Cleveland now enter a summer of uncertainty with the futures of Mitchell and coach J.B. Bickerstaff in the spotlight.

Mitchell is eligible to sign a contract extension, but has not given any indication that he is eager to stay or leave Cleveland.

Bickerstaff is completing his fourth full season as Cleveland's coach.