DALLAS - 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 minutes, 45 seconds remaining, and the Mavericks beat the Heat, 112-103, on Thursday night to take a three-games-to-two lead in the Finals.

Five years after going up by 2-0 on the Heat, the Mavs finally got that elusive third victory, and can wrap up their first championship in Game 6 at Miami on Sunday night.

"We're a very resilient team, you know that," guard Jason Terry said. "We've been in tough battles all playoffs long. It's not going to stop. It's going to get even harder. But we're ready. We're determined, and this is our time."

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.

They get the final two games at home, but history is against them as they try to win a title in their first season together: In the 26 previous times the Finals were tied 2-2, the Game 5 winner won 19 of them.

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.

This time, they got to play from ahead thanks to some sizzling shooting: 56.5 percent from the field, including 13 of 19 (68 percent) from three-point range.

Terry scored 21 points, and J.J. Barea had 17 for the Mavs.

"I felt great. I felt great. I was in rhythm tonight," Terry said.

An Iverson comeback?

Ten years after he ruled the NBA as the MVP who led the 76ers to the Finals, Allen Iverson is eyeing a comeback.

Iverson turned 36 on Tuesday. He played only 10 games in an injury-filled stint in Turkey after a lack of NBA interest forced him to seek employment elsewhere. In his most recent NBA season in 2009-10, Iverson left the Sixers in February.

What gives Iverson confidence he can still play anywhere near his former elite level next season?

"It's me," he said, laughing. "That's what gives me confidence."

All-star Mitchell dies

Former NBA all-star Mike Mitchell, 55, who played 10 seasons for the Cleveland Cavaliers and the Spurs, died Thursday in San Antonio, Texas, after a two-year struggle with cancer.

The former Auburn star averaged 19.8 points during his career. He was an all-star in Cleveland in 1981.

Pistons talking to Sampson

The Milwaukee Bucks have given the Detroit Pistons permission to interview assistant Kelvin Sampson for their vacant head coaching job, a person with knowledge of the situation told the AP.

NBA Report

GAME 5

Heat 103 Mavericks 112

Dallas leads series, 3-2.

 Next: Mavericks

at Heat, Sunday

at 8 p.m.