DALLAS(AP) Run-and-gun offense used to be the Denver Nuggets' trademark. Now they are winning with defense.

Reserve J.R. Smith scored 25 points, Carmelo Anthony added 23, and the Nuggets beat the Dallas Mavericks 98-88 on Monday night to extend their winning streak to four games.

Chauncey Billups had 15 points and eight assists for the Nuggets, who have won seven of eight and improved to 16-4 since Billups joined the team after a Nov. 3 trade with the Detroit Pistons.

Dirk Nowitzki had 27 points and 10 rebounds, and Jason Terry scored 19 points for the Mavericks, who had won 11 of their previous 13.

Dallas shot a season-low 35 percent from the field. The Nuggets are 10-1 when they hold an opponent under 100 points and improved to 8-1 when an opponent shoots below 40 percent.

"We don't win tonight without the defense,'' Denver coach George Karl said.

The arrival of Billups has given that defense a lift.

"(Defense) was our main focus coming in,'' Billups said. "We knew coming in that this team is as good an offensive team as you'll find, so us being locked in and tuned into the game plan was important. We were able to contest all their shots. With an offensive team that's free-flowing, you can't let them get to their sweet spots.''

Denver's defensive rotations confused the Mavericks at times.

"They do a lot of switching,'' Terry said. "That defense shouldn't be effective against us. And our defense was horrendous.''

Mavericks forward Josh Howard was back after being inactive for 11 straight games because of a sprained left ankle. He came off the bench late in the first quarter and played 14 minutes, scoring seven points.

Dallas coach Rick Carlisle will ease Howard back into the starting lineup. Howard admitted some "discomfort'' but he said that overall, "It felt good. Any time you're out for a while, you have to get back into a rhythm.''

Denver opened the fourth quarter with a 12-0 spurt, including eight from Smith, for an 87-71 advantage. The Mavericks never got closer than eight the rest of the way.

Nowitzki scored Dallas' first 11 points of the third quarter, continuing his run of 16 straight points that started in the second quarter, to narrow Denver's advantage to 61-54.

Nowitzki had 16 points in the third quarter, but Denver carried a 75-71 lead into the fourth.

The Nuggets grabbed a 27-15 first-quarter lead behind Anthony's 12 points and the team's 11-for-18 field goal accuracy. Dallas went 6-for-25 from the floor in the first quarter.

The Mavericks set a season low for first-quarter points and shot 29 percent from the field in the first half (13-for-45), with Nowitzki going 3-for-9.

Dallas got within four, but Denver closed with a 16-7 run for a 56-43 lead at the break.

"Our undoing was the first quarter,'' Carlisle said. "It speaks to the importance of good starts, not playing from behind. Offensively, we couldn't hit a bull in the butt with a bass fiddle. We just weren't good enough.''

Notes: Mavericks opponents were shooting 30.2 percent from 3-point range, but the Nuggets connected on 10-of-19 (53 percent). ... Dallas' Erick Dampier had 15 rebounds, his third game with at least 15 boards this season. ... Howard, whose last game was Nov. 18, entered the game as Dallas' No. 2 scorer at 20.3 ppg. ... Freezing rain in the Dallas area kept several hundred ticket-buyers home. ... Denver won for only the third time in its last 20 visits to Dallas since 1997-98.

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