DALLAS » The Miami Heat have bigger problems than the disappearance of LeBron James. The entire team has gone missing.

Just when it looked like it couldn’t get any worse, it did, Dwyane Wade limping in and out of the lineup as the Heat moved within a loss of Miami mourning.

In the series that won’t stop spitting out subplots, the Dallas Mavericks kept taking it to the Heat, this time a 112-103 victory Thursday for a 3-2 lead in the NBA Finals.

The Mavericks are a victory away from the first championship of their 41-year existence.

Can’t imagine Mark Cuban getting much sleep before Sunday, when the series shifts back to Miami. Can’t imagine anyone at all sleeping peacefully on the Heat.

Seeing how James can’t find his scoring touch, the most important people in South Florida the next few days are the Heat trainers.

Wade bruised a hip after colliding with Brian Cardinal late in the first quarter, and neither he nor the Heat ever quite straightened out.

Small forward Mike Miller started for Wade in the third quarter, meaning the Heat went with one guard.

Bad idea.

With Wade in the locker room the first seven minutes of the third quarter, the Mavericks’ guards sizzled.

Jason Terry had 21 points and Jose Barea had 17 points. The Mavericks made 13 of 19 three-point shots (68.4 percent).

Dirk Nowitzki had his usual 29 points, shaking off whatever remained of that 101-degree fever as fans regaled him with “NoQuitzki” and “Dirk Fever” signs.

And is there a more automatic thing these days than Nowitzki at the free-throw line? He shoots, he gets fouled, he makes his free throws.

He’s 43 of 44 in the Finals after going 10 for 10 in Game 5. That’s 97.7 percent.

“Persistence is our game,” Dallas Coach Rick Carlisle said. “We’re an old-school team. We’re not high fliers. Our game is near the ground. We have to play with brains and guts.”

It’s tough to ascertain Miami’s mind-set, but the Heat will have to be gutsier.

James was very solid in the intangibles — 10 rebounds, 10 assists toward the first triple-double in Heat playoff history — but had only 17 points on 8-for-19 shooting. He was caught with another unexcused absence in the final quarter — two points, 1-for-4 shooting.

He was resolute afterward when asked if the pressure was getting to him.

“No, I don’t think so. I don’t believe so. I know I’m not,” he said. “We as a team, we played good enough to win again. They just made a few more (plays) than we did. That’s what it came down to.”

Wade had eight points in the first eight minutes but slowed down after his injury, finishing with 23.

If he’s not healthy for Game 6, the Heat might be cooked.