PORTLAND, Ore. -- All 82 regular-season games are important, but some loom a little bigger than the rest.

That was the case Wednesday night at the Moda Center, with sixth place in the tightly bunched Western Conference playoff race on the line.

So there was cause for celebration in the Portland Trail Blazers' locker room after their 109-103 victory over the Dallas Mavericks.

"This is the time of year when (regular-season) games mean the most," said Portland point guard Damian Lillard, who scored 27 points to go with six assists and six rebounds. "We're in a tight playoff race that's almost over. (The Mavericks) could have passed us up with a win, could have swept us for the season, and we're going (to Los Angeles) to play the Clippers (Thursday night).

"It could have been a tough spot to be in, but we said, 'We're going to play the kind of basketball we need to play and get this one.'"

Power forward Ed Davis came off the bench to score all of his 16 points in the first half. He also finished with nine rebounds for the Trail Blazers (37-35), who fell 132-120 in overtime Sunday at Dallas.

Former Blazers guard Wesley Matthews scored 22 points for Dallas (35-36), which lost for the sixth time in nine games. Dirk Nowitzki added 21 points and nine rebounds, Salah Mejri collected 14 points and 12 boards, and Deron Williams contributed 12 points and 11 assists for the Mavericks, whose 17 turnovers resulted in 22 Portland points.

"I liked the way we competed," Nowitzki said. "We just couldn't overcome some of the mistakes we made. Every time we turned the ball over, it was pretty much a layup at the other end."

Matthews who sank eight of 15 shots from the field, including six of 10 from 3-point range, received a standing ovation from the fans during pregame introductions.

"Much love and appreciation and respect to them," he said. "Would have felt better to get the win, though. It was a big game, but we have 11 more big games. Got to learn from this one and move on."

Davis led Portland to a 57-53 lead at intermission. Lillard contributed 11 points and five assists for the Blazers in the first half. Matthews had 14 points for the Mavericks at the break.

Portland scored the first five points of the third quarter to go ahead 62-53, but the Mavericks hung in, closing within 68-64 on a Matthews 3-pointer. The Blazers answered with eight consecutive points to make it 76-64. They had an 83-73 edge heading into the final period.

The difference was 93-78 after a fastbreak dunk by Portland's Al-Farouq Aminu with 7:45 remaining. The Mavericks rallied, and Matthews' sixth 3-pointer of the game brought them within 101-95 with 1:44 to play.

After Portland's Allen Crabbe and Nowitzki traded triples, Lillard sank a pair of free throws to give Portland a 106-98 lead with 26 seconds to go. Nowitzki converted a three-point play with 18.7 seconds left to make it 106-101. CJ McCollum then wrapped it up with two foul shots for the Blazers with 15.8 ticks left.

"A really big win for us," Portland coach Terry Stotts said. "We did a lot of good things. We had some breakdowns here and there, but I liked our energy, I liked our fight, I liked our resilience bouncing from last game. This was a game we needed to have."

NOTES: The Trail Blazers earned only their fourth win in 11 outings. ... Dallas was without F Chandler Parsons (knee), who could be lost for the season. Parsons also missed the Mavericks' 132-120 overtime win over Portland on Sunday. ... Portland F Meyers Leonard (shoulder) sat out his fourth consecutive game. ... Dallas shot 43.8 percent from the field and 30 percent (9-for-30) from 3-point range. Over the previous 10 games, Portland opponents averaged 116.7 points. In the past eight, Blazers foes shot 49 percent from the field and 46.7 percent from beyond the arc. ... C Salah Mejri, a 29-year-old rookie from Tunisia, had 13 points, 14 rebounds and six blocked shots in 32 minutes off the bench in the Mavericks' Sunday victory. ... Dallas coach Rick Carlisle, on playing the Blazers' back to back: "It's like a mini-playoff series."