Mavericks coach Rick Carlisle has praised his team's balance on offense this season, but Nowitzki's still the go-to guy with the game on the line.
"He's the classic case of a great player and you just stay the course," Carlisle said. "I played with Larry Bird for three years and there were nights when he'd go 2 for 13 and then hit the last three shots to win the game. Dirk's the same kind of guy."
Caron Butler of the Clippers scored a season-high 23 points against his former team, and just missed a 3-pointer with less than 5 seconds left that would have put the Clippers in front. Teammate Blake Griffin added 20 points, but Griffin's problems from the free-throw line cost his team as he missed seven of nine foul shots.
"He's been shooting it real well," Clippers coach Vinny Del Negro said. "I was surprised they went to foul him. ... It was just one of those nights."
Chris Paul had 16 points and nine assists for the Clippers, who completed a 4-2 road trip. They haven't beaten the defending NBA champs in Dallas since April 19, 2006.
Dallas took control with a 7-0 fourth-quarter run capped by Marion's layup with 4:48 remaining for an 86-83 edge.
Griffin had a chance to get the Clippers closer, but missed five straight free throws until connecting with 2:15 to play to pull his team within two points at 86-84.
Jason Kidd set up Terry for a layup with 2:02 left, and Nowitzki intercepted Griffin's pass with 1:47 showing, and drained two free throws to extend Dallas' edge to 90-84.
Griffin's three-point play with 1:24 remaining and Kenyon Martin's layup with 1 minute left narrowed the Mavericks' lead to 90-89.
Nowitzki drained a 19-footer from the right wing and, after Marion stole the ball from Martin, converted two free throws with 21.2 seconds left for a 94-89 advantage.
"I had some looks I've got to make," said Nowitzki, who missed five of seven shots in the final quarter, but got to the free-throw line seven times, converting six.
Paul's 3-pointer with 17.8 seconds got the Clippers within two points, and Butler's 3-pointer from the right wing missed with 4.5 seconds left.
"It felt real good," Butler said of his final shot. "I had my feet under me. It just fell short. It would have been a great ending."
Delonte West made two free throws with 2.9 seconds remaining to seal the victory.
Dallas' defense came up big in the fourth quarter, causing seven turnovers and limiting the Clippers to 5-of-15 shooting from the floor and making it tough for Paul to pass his signature lob passes for dunks by Griffin.
"We take it to heart as a team," Haywood said of the Mavs' defense. "We don't want teams coming on our home floor showboating. When a team comes in like this, we want to make it hard to get to the rim."
Haywood worked inside for 10 of Dallas' first 22 points and the Mavs carried a 27-19 lead into the second quarter.
Butler, who received a championship ring from the Mavs in pregame ceremonies, got rolling early when he connected on his first three 3-point attempts in the first quarter.
Carlisle introduced Butler to the crowd before the game, and hugged Butler as the player tried on his ring.
"It was more emotional than I thought it would be," Butler said.
The Clippers ended a 10-game overall losing streak against the Mavs on Jan. 18 with a 91-89 win in Los Angeles. Chauncey Billups hit the winning 3-pointer with 1 second left. Billups is out for the season with a torn left Achilles' tendon sustained in a game on Feb. 6.
Butler was a member of the Mavericks' title-winning team last season but missed the final 53 games of the regular season plus the playoffs with a ruptured right patellar tendon. Butler, signed by the Clippers in December as a free agent, made a spirited effort to get his knee healthy enough to contribute for Dallas in the playoffs and Carlisle said before the game that Butler "was very close to being active for the finals. That's how hard he worked." ... Martin, who grew up in Dallas, played his fourth game for the Clippers since signing as a free agent on Feb. 3. ... Before the game, Carlisle called Paul "the best playmaker in basketball."