Luka Dončić scored 25 of his 29 points in a dominant first half and the Dallas Mavericks rolled to a 122-84 rout of the Boston Celtics to avoid a sweep in Game 4 of the NBA Finals on Friday night.

Kyrie Irving added 21 points and Tim Hardaway Jr. scored all 15 of his in the fourth quarter for the Mavericks, who forced the series back to Boston for Game 5 on Monday night.

Dallas opened a 13-point lead after one quarter, were up 26 at halftime and led by as many as 38 in the third before both sides emptied their benches.

Dereck Lively had 11 points and 12 rebounds for the Mavs, and connected on the first 3-pointer of his NBA career midway through the first quarter.

The 38-point final margin was the third-biggest ever in an NBA Finals game, behind only Chicago beating Utah 96-54 in 1998 and the Celtics beating the Lakers 131-92 in 2008.

Jayson Tatum scored 15 points and Sam Hauser had 14 for Boston, which had its franchise-record, 10-game postseason winning streak snapped.

The Celtics shot 36.3 percent (29 for 80) from the field and were outrebounded 52-31.

The 35 points in the first half represented their lowest-scoring total in a half in Joe Mazzulla’s two seasons as coach. The 26-point deficit at halftime was Boston’s largest ever in an NBA Finals game.