The AP reports:

Dirk Nowitzki

Dirk Nowitzki and the Dallas Mavericks finally have the lead in these ultra-close NBA finals, and now it really is “now or never” for LeBron James and the Miami Heat.

Nowitzki scored 29 points, driving for the go-ahead dunk with 2:45 remaining, and the Mavericks beat the Heat 112-103 on Thursday night to take a 3-2 lead in the NBA finals…

James, who called this game “now or never,” responded from his worst playoff performance with 17 points, 10 rebounds and 10 assists, and Dwyane Wade battled through a sore left hip after a first-quarter collision to finish with 23 points…

The Mavs shot 60 percent through three quarters, briefly gave up the lead in the fourth, then controlled the final few minutes, just as they had in thrilling comebacks in Games 2 and 4…

Terry scored 21 points and J.J. Barea had 17 for the Mavs, with Nowitzki briefly throwing both arms in the air as he walked off the court surrounded by a sea of blue fans who hope he’ll bring home a championship trophy if they can pull out another victory in Miami…

The Mavs tied it at 100 on Terry’s 3-pointer with 3:23 left, and after James missed, Nowitzki drove for a baseline dunk and a 102-100 lead with 2:45 to go. James was called for an offensive foul and missed a 3-pointer on Miami’s next two possessions before Kidd drilled a 3-pointer to make it 105-100, sending the crowd into a delirious chant of “Beat the Heat! Beat the Heat!” …

Wade walked gingerly to the locker room with a left hip contusion with about 3 minutes left in the period after colliding with Mavs reserve Brian Cardinal on a drive to the basket, and didn’t return to the bench until more than 3 minutes into the second. But the Heat hung in while he was gone, even taking a 31-30 lead when the Mavs turned it over on their final possession and Mario Chalmers threw in a heave from just inside midcourt to beat the buzzer, nearly a duplicate of the finish of the first quarter in Game 3 that stunned Dallas.

Joseph Goodman of the Miami Herald reports:

The Heat shot 53 percent in the third quarter but was outscored 24-22. Barea provided the spark for the Mavericks in the third quarter, leading his team with eight points on 3-of-4 shooting and 2 of 3 from three-point range. Dallas was 4 of 7 from three-point range in the third quarter.

Wade remained in the locker room after halftime and didn’t emerge until less than five minutes remained in the period. He entered the game with 4:33 left in the quarter but managed to contribute a field goal. Wade entered the fourth quarter with 13 points while Bosh, James and Mario Chalmers each had 15.

The drama of the first half simply seemed like an extension of the exciting conclusion of Game 4. Mario Chalmers, of all people, kept the Heat in the game. His three-point shooting—4 of 6 from behind the arc — nearly matched the Mavericks’ effort as a team (5 of 7).

Chalmers, underappreciated among the Heat’s veteran roster, has played better than any point guard in the NBA Finals, including future Hall of Famer Jason Kidd. Chalmers finished the first and second quarters with clutch three-pointers, including a 40-footer at the first-quarter buzzer.