CHICAGO -- The Toronto Raptors did not score fewer than 95 points in their first 13 December games.
In their last game of the month, they won despite a lack of offense.
Center Jonas Valanciunas scored 15 points and led a strong defensive effort in the fourth quarter as the Raptors beat the Chicago Bulls 85-79 at the United Center.
The Raptors opened the fourth quarter with a 21-4 run to take control. The Bulls shot just 16.7 percent (4-for-24) from the field in the final quarter.
"It was a game of toughness and physicality that you have to play if you are going to be in the playoffs," Toronto coach Dwane Casey said. "That is how we will have to play to get there."
Guard Kyle Lowry added 13 points and DeMar DeRozan scored 11 for Toronto, which earned its eighth win in 11 games.
With their second win at the United Center in 17 days, the Raptors (14-15) improved to 9-7 on the road this season. Toronto has never posted a winning road record during 19 seasons as a franchise.
Forward Luol Deng, back after a five-game absence caused by a sore left Achilles tendon, led Chicago with 16 points, while guard Jimmy Butler added 15. Center Joakim Noah added 16 rebounds, seven points and a team-high six assists.
"I didn't feel tired out there, just my rhythm, my timing was a little bit off," Deng said. "I missed a couple of shots I would normally make and a couple of plays I would normally make."
Toronto trailed 62-57 heading into the fourth quarter. Forward Patrick Patterson followed in his own miss and began a string of six straight made shots by the Raptors.
A 3-point pull-up by guard Greivis Vasquez put Toronto ahead 66-64. A few minutes later, Patterson hit a turnaround in the lane, boosting the advantage to 78-66 with 4:43 remaining.
"We just played like a team," Valanciunas said. "We got it together and we trusted each other."
Chicago closed within 80-75 when Butler poked the ball loose, scored on a fast-break lay-in and finished a three-point play. After Deng's free throws made it 80-77 with 1:24 left, Toronto got three big defensive stops.
"You have to kick butt when they come into the paint," Casey said. "That's what J.V. did tonight."
DeRozan and forward John Salmons combined to miss three of four free throws, keeping the Bulls alive. However, Valanciunas knocked down two at the line and DeRozan added one of two to push the Raptors' edge to 84-77.
The Bulls (12-18) matched their largest lead at 56-47 with 4:52 left in the third quarter on a short jumper by Noah.
With Deng back in the starting lineup, Chicago got a better performance from the bench. Forwards Taj Gibson and Mike Dunleavy, guard D.J. Augustin and center Nazr Mohammed combined to score 25 of the team's 42 points in the first half. However, the quartet added just eight second-half points.
"The problem you have is when guys miss an amount of time and then come back, it takes a while to get in rhythm," Chicago coach Tom Thibodeau said. "That's what opens up the inside. We had a hard time scoring."
The Bulls were playing the second leg of back-to-back games after beating the Grizzlies in Memphis on Monday. Toronto was off since Saturday and will face the Indiana Pacers at home on Wednesday.
NOTES: Chicago F Luol Deng was back in the starting lineup after missing nine of the previous 12 games with a sore left Achilles tendon. The Bulls used a starting lineup of Deng, G Kirk Hinrich, G Jimmy Butler, F Carlos Boozer and C Joakim Noah -- the projected lineup, minus G Derrick Rose -- for just the second time this season. ... Toronto played at the United Center on Dec. 14 and beat the Bulls 99-77. ... Officials rescinded a flagrant foul against Chicago C Nazr Mohammed in the first half after viewing the replay. Mohammad bit on a pump fake and grabbed Toronto C Jonas Valanciunas by the shoulders, spinning him to the ground. ... The Bulls finished with a 36-26 advantage on points in the paint.