Dirk Nowitzki had 21 points and 10 rebounds, Shawn Marion added 18 points, and Dallas stretched its winning streak to 11 games with a 102-89 victory over the New Jersey Nets on Thursday night in Johnson's return to Dallas.
Johnson, fired by the Mavericks after the 2007-08 season, is in his first season with the Nets.
Jason Terry and Caron Butler added 15 points each, and J.J. Barea had a career-high 13 assists to help the Mavericks extend the NBA's longest current winning streak.
"I got to shake his hand and hug him before the game," said Terry about Johnson, who became the Mavericks' coach late in the 2004-05 season, and led Dallas to its only trip to the NBA Finals in 2006 when the Mavs were beaten by the Miami Heat in six games.
"I actually thought it would be even a little more emotional. But it subsided as we got into the flow."
Barea got his start in the NBA with Johnson as his coach.
"He was the guy that gave me a chance to be in the NBA," Barea said. "He showed me a lot my first two years here, so it's always special."
Brook Lopez led New Jersey with 24 points, Anthony Morrow had 21, and former Maverick Kris Humphries finished with 16 points and 13 rebounds. The Nets have lost six straight and 11 in a row on the road.
Johnson admitted his first game in Dallas since his firing meant more to him than a standard regular-season visit, but the short-handed Nets had a tough time handling the veteran Mavericks.
"It was pretty emotional," said Johnson, who hugged several Mavericks as the teams left the court. "A lot of friends and family are here tonight...but it was good seeing some of the guys."
New Jersey point guard Devin Harris sat out the final three quarters because of a sprained left shoulder. Harris, who played for the Mavs from 2004-08, was injured when he tried to deflect an alley-oop pass to Tyson Chandler and fell to the floor. He was scoreless in 9:22.
Harris said he hoped to play in New Jersey's next game Sunday at home against the Los Angeles Lakers.
"It doesn't feel good," Harris said. "It's the one part of the body I wish I didn't hit was the left shoulder. It was just a tough play. I kind of used him to brace myself up to get the ball, but he wasn't there to break my fall, fell kind of hard. I was going to try and give it a go, but coach thought otherwise."
New Jersey also was without rookie forward Derrick Favors, sidelined by a bruised thigh. Favors, the third overall pick in the June draft, was hurt Tuesday night in a loss at Atlanta.
The Mavs pushed their lead to 21 points early in the third quarter, but the Nets cut it to 79-69 with a 28-17 run over the final 9:53 of the quarter. New Jersey caught up by driving to the basket and getting fouled, going 15 for 18 from the free throw line in the third quarter.
New Jersey crept as close as 81-73 early in the fourth quarter, but Terry's basket with 6:04 left capped a 13-3 run for a 94-78 lead.
"(The Nets) hung in," Mavs coach Rick Carlisle said. "They played hard and kept grinding. We did the same and were able to get the win."
Dallas shot 72 percent from the floor (13 for 18) to grab a 30-19 lead after one quarter.
The Mavs were up by 18 in the second quarter and carried a 55-40 edge into the break with the help of a 19-3 advantage in fast-break points.
Marion went 6 for 6 from the field in the first half, and Dallas was 24 for 37 (64.9 percent).
NOTES: Dallas has won its last 11 at home against New Jersey. The Nets' last victory in Dallas was on March 2, 2000. ... Chandler returned to the starting lineup after missing the previous game with a stomach virus. Chandler is still feeling the effects of the illness and lacked energy, finishing with two points, five rebounds and five fouls... Nets rookie F Damion James got his first NBA start. James played for the University of Texas. ... Johnson said Favors will try to practice Saturday with the aim of returning Sunday against the Lakers. ... Dallas' longest winning streak is 17 games.