Nowitzki shook off a shoulder issue in the first minute to finish with 18 points, but Davis was knocked out of the game with a similar problem and the Mavericks beat the Pelicans 108-89 Wednesday night.
"I'm thinking Dirk's going to be out when he goes out with a shoulder injury and then a few plays later AD gets hit and he's out," said New Orleans coach Monty Williams, who could now be without three of his top four scorers. "Dirk comes back. So, it just hasn't gone our way."
Nowitzki left the court 31 seconds into the game but emerged a short time later and returned to the game. He even had a spin move and finished with a left-handed finger roll in the first half.
"I've had it ever since Karl Malone hacked me in '99," said Nowitzki, who was favoring the shoulder after throwing an alley-oop pass to Sam Dalembert for a layup on the first possession. "The shoulder just sometimes comes in and out a little bit. It's happened a good 20 times already over my career."
Davis, the leading scorer and rebounder for the Pelicans, was holding his sprained left shoulder on his way to play defense and didn't return after leaving the game during a New Orleans timeout with 4:13 left in the first half.
After the game, Williams didn't have an update on the condition of his All-Star big man, who was on the bench during the second half with his left arm in a sling.
"When you play as hard as AD and these guys who go after it every single night, they're going to have bumps and bruises," Williams said. "It could be nothing. It could be a day-to-day thing. We've got to let the doctors do their deal."
The Mavericks (36-23) are a season-high 13 games over .500 after their fourth straight win, and the Pelicans stayed winless since the All-Star break at 0-5.
"Monta has been doing a great job I think picking his spots, attacking when it's there," Nowitzki said. "He's been great for us all season making plays off the dribble and getting in the lane."
The injury to Davis is the latest in a litany of them for the Pelicans.
Second-leading scorer Ryan Anderson is likely out for the season with a herniated disk. Jrue Holiday, another double-digit scorer and New Orleans' assists leader, is sidelined after breaking his right shin in early January.
Davis, who averages 20 points and 10 rebounds per game and leads the NBA in blocked shots, was sharp early to help the Pelicans build an eight-point lead. He had six points to go with a game-high nine rebounds and two blocks in just 12 minutes.
"It's difficult, but guys have been in and out all year," Gordon said. "We've just got to keep on adjusting."
Even when they had Davis on the floor, the Pelicans couldn't protect the ball while getting swept in the four-game season series with Dallas. They had a season-high 19 turnovers after committing at least 16 in each of the previous three meetings.
One of New Orleans' turnovers ended with a pass to Nowitzki standing alone under the basket for a dunk and an 84-69 lead early in the fourth quarter.
Nowitzki was 7 of 13 from the field two nights after he hit his first game-winning shot at the buzzer since 2009 to beat the Knicks in New York and finish a 3-0 trip through the Eastern Conference.
The big German led the Mavericks with eight points in the third quarter, when they took their first double-digit lead. Dallas put away its 10th win in 12 games with a 15-2 run to start the fourth.
"We've done better over the last couple of weeks," Mavericks coach Rick Carlisle said. "But we've got a long way to go."
NOTES: New Orleans C Alexis Ajinca had 14 points and eight rebounds in his first game after setting career highs with 19 points and 12 rebounds in loss to the Los Angeles Clippers. ... Ellis led the Mavericks with eight points in the second quarter, when they turned an eight-point deficit into an eight-point lead before settling for a six-point edge at halftime.