LOS ANGELES (AP) -- The Los Angeles Lakers have their longest winning streak in nearly four years, but for now, that's the last thing on their minds.
Andrew Bynum, a key factor in the team's ascent to elite status at this stage of the season, sprained his left knee early in the third quarter of Sunday night's 100-99 victory over the Memphis Grizzlies, and will undergo an MRI on Monday to determine the severity of the injury.
The 20-year-old center expressed the opinion as he left Staples Center following the game that his injury isn't serious, but perhaps that's simply wishful thinking.
"I feel all right," he said, walking under his own power, although limping slightly, with a brace on his left leg while personal trainer Sean Zarzana carried a pair of crutches.
"It's on the top of the kneecap, and a little on the right," Bynum said. "I was pretty scared. But the X-rays were negative. I never heard a pop. Just when I bend it, it hurts. I'm feeling fine, it's not as bad as I thought. I put ice on it, and it felt better right away."
Kobe Bryant scored 37 points, and Kwame Brown made a foul shot with 9.2 seconds remaining as the Lakers extended their winning streak to six, their longest since they won 11 straight late in the 2003-04 season before going on to reach the NBA finals. They haven't won a playoff series since that time.
Brown, a 38-percent foul shooter, connected on his first attempt to snap a 99-all tie before missing the second. The Grizzlies had two shots at winning the game, but Kyle Lowry missed a runner in the lane and Hakim Warrick was way off the mark on a 3-pointer as time expired.
Bynum was helped off the court after coming down on teammate Lamar Odom's left foot while going for a rebound under the Memphis basket. Bynum dropped to the floor in obvious pain, clutching his knee.
Bynum had 10 points, nine rebounds and three assists and the Lakers led 66-55 when he was injured. Teammates Brown and Ronny Turiaf carried him to the locker room, and the 7-footer wasn't putting any weight on his left leg as he left the court.
"We do know that Andrew's had a knee problem in the past, when he was a kid," Lakers coach Phil Jackson said. "We do know there's some liability there. It's the other one, from what I understand."
Odom and Jordan Farmar scored 10 points each for the Lakers, who have won 16 of their last 19 to move within a half-game of Phoenix and Dallas, the Western Conference co-leaders. At 25-11, the Lakers are 14 games over .500 for the first time since they were 56-26 at the completion of the 2003-04 season.
How long they'll be without Bynum is unknown, but a serious injury would make it difficult for them to continue the kind of success they've experienced since early December.
"It's unfortunate. It's part of the game," Bryant said. "It happens to all of us. It's going to change our rhythm up a lot. The next couple games or a week or so might be a little shaky. That's good that he's walking. The important thing is to stay on top of it."
Brown figures to start at center in Bynum's absence, with Turiaf serving as the backup center. Chris Mihm is sidelined for at least two more weeks with bursitis in his right ankle.
The win was the 944th of Jackson's career, tying him with Bill Fitch, his coach at the University of North Dakota, for sixth place on the NBA's list.
"One thing I have to admit I really like about this team is that they fight back all the time, no matter what happens," Grizzlies coach Marc Iavaroni said. "Under their control or not under their control, they've proven to be real fighters."
Warrick made two free throws with 1:53 remaining to give Memphis a 96-95 lead. Bryant made a pair with 1:02 left to put the Lakers back in front, and added a layup with 42 seconds to go.
Rudy Gay's 3-pointer with 32 seconds remaining tied it at 99, setting the stage for Brown.
The Lakers led by 13 points early in the fourth quarter before the Grizzlies scored 14 straight to put them ahead 88-87 -- their first lead early in the second period. Neither team led by more than three points after that.
The Lakers led by as many as 14 points in the third quarter before settling for an 80-70 lead entering the final period.
Bryant became the 44th player with 1,000 career 3-pointers with his first of three in this game. The 3-pointer was introduced in the NBA before the 1979-80 season. ... This is the first time the Lakers have started a calendar year with six wins since accomplishing the feat in 2002. The franchise record for most consecutive wins to start a new year is nine, set in 1963. ... The Grizzlies are winless in six games against Pacific Division teams this season. ... The Lakers also beat the Grizzlies 117-101 in Memphis last Tuesday night. The Grizzlies had won eight of the previous 11 games between the teams. ... Turiaf celebrated his 25th birthday Sunday. ... Lakers F Vladimir Radmanovic missed his sixth game because of a sprained right ankle.