DALLAS -- After a stretch of close games and frustrating losses, the Dallas Mavericks got exactly what they needed on Sunday night.

Wesley Matthews scored 21 points, Dirk Nowitzki had 18 and the Mavericks led by as many as 30 points in a 129-103 win over the Philadelphia 76ers.

Dallas had played three straight overtime games and lost five of six coming into the night, but it put away Philadelphia with a big second quarter and coach Rick Carlisle went deep into his bench in the final period.

All 12 Mavericks scored, six in double figures, in Dallas' highest scoring game of the season. It also was the Mavericks' largest margin of victory this year.

"We needed a win," Nowitzki said. "There was some frustration building from some close losses where we should have won. We definitely needed a win to stop the bleeding."

Dallas could get another lift on Monday with the addition of forward David Lee, who was waived by Boston. Mavericks coach Rick Carlisle said Lee had arrived in Dallas and was expected to sign with the team.

The Mavericks' biggest challenge Sunday was stopping Jahlil Okafor, who scored 18 points in the first quarter and finished with a career-high 31. Okafor's total was not only his highest as a pro, but one more than his high total during his one-and-done national championship season at Duke last year.

"The team was giving me the ball in great position to score, and I was just trying to keep being aggressive," Okafor said.

The Sixers led 43-35 in the second quarter before Dallas closed the half with a 31-11 run. The 66 points were Dallas' best half of the season.

The Mavericks' aggressive play got them to the line frequently. They made 16 of 17 free-throw attempts in the second quarter and finished the game 34 of 36 at the line.

"We were playing with a swagger and a confidence that we haven't done often enough at home," Matthews said. "It's tight right now as far as the playoff picture. The season is a marathon, and we're in the sprint part right now."

Philadelphia closed to 80-71 on Nik Stauskas' 3-pointer with 5:09 left in the third, but the Mavericks scored the next 10 points.

BRINGING ON LEE

The Mavericks were excited at the prospect of bringing on another veteran presence in Lee.

"Obviously he's a champion," Matthews said. "He's a great rebounder and inside presence. He knows the game and hopefully he can add to this team."

ANOTHER DIRK MILESTONE

Nowitzki went over 29,000 career points with a 3-pointer with 10:21 left in the third quarter. He is sixth in scoring in NBA history.

"It means you've been around for a long, long time and you've put in a few baskets here and there," Nowitzki said. "I've been fortunate to be with this franchise for so long and stay injury free for the most part."

TIP INS

76ers: Forward Jerami Grant played despite being poked in the eye for the third time this season on Friday night. Coach Brett Brown, when asked what Grant has shown him this season, quipped: "He's shown me that he needs goggles." ... The Sixers have lost their last seven games against Dallas.

Mavericks: Dallas will release guard John Jenkins to make room for Lee. ... Devin Harris returned to the lineup after missing the past 10 games with a left big toe strain. Deron Williams started for the Mavericks despite a right calf strain.

UP NEXT

76ers: Host Orlando on Tuesday.

Mavericks: Host Oklahoma City on Wednesday.