Charlotte Bobcats forward Emeka Okafor is expected to be out at least another five weeks with a sprained right ankle that has already cost him 19 of the last 20 games.

The reigning NBA Rookie of the Year originally sprained his ankle Dec. 19 and missed eight games. He returned on Jan. 10, but was re-injured in the Bobcats' double overtime win over Houston. Charlotte hasn't won a game since.

Also, forward Gerald Wallace (knee bruise) and guard Keith Bogans (knee sprain) are expected to be out another two to four weeks with their injuries.

Charlotte Bobcats guard Brevin Knight was knocked out of Friday night's game against the Miami Heat with a mild concussion.

Knight was injured in the first quarter when he ran into Miami's Gary Payton and fell to the floor. Replays appeared to show Payton accidentally elbowed Knight in the back of the head.

Knight finished out the first half, but spent several minutes talking with the team physician before the second half resumed.

The Charlotte Bobcats have added yet another name to a long list of injured players.

Keith Bogans suffered a Grade 1 right MCL sprain in Saturday's game at Milwaukee.

The 6-5 guard suffered the injury in the second quarter of Charlotte's 101-91 loss. No timetable was given for his return.

"It is unfortunate that we have suffered another injury but we will continue to play hard and compete with the group that we have," Charlotte general manager and coach Bernie Bickerstaff said. "Keith has played well for us this season whenever he's been called upon and we will miss him during his injury."

The Bobcats are already without leading scorer Gerald Wallace (knee), starters Emeka Okafor (ankle) and Kareem Rush (finger) and reserve forwards Melvin Ely (ankle) and rookie Sean May (knee surgery).

The injuries keep piling up for the Charlotte Bobcats.

Forward Gerald Wallace suffered a left medial tibia bone bruise in Friday's 104-93 loss against Orlando and will be sidelined indefinitely, the team announced Saturday.

An MRI following the game revealed the bone bruise. No return date has been set but it could be as long as six weeks.

Wallace become the latest player added to the injury list for the Bobcats, who are already playing without forwards Emeka Okafor, Sean May and Melvin Ely and guard Kareem Rush.

Wallace suffered the injury at the 5:50 mark of the third quarter when he fell to the ground after going for a rebound. He finished with 12 points, seven rebounds and two steals.

"The good news is that this is a different injury than we originally thought, but it is still an injury we have to let take its course in recovery," Charlotte general manager and coach Bernie Bickerstaff said. "Gerald is having a tremendous season and we expect him continuing that when he returns, but we will be patient in letting his bone bruise heal fully and keep the long term in our minds."

Charlotte Bobcats forward Sean May had arthroscopic surgery on his right knee Thursday, likely bringing his rookie season to an end.

May, the 13th overall pick in the NBA draft, had missed the past 13 games because of soreness in his knee. He had surgery on the knee on Sept. 13 in California, then Charlotte officials scheduled Thursday's procedure to explore why it was still bothering him.

Bobcats physician Dr. Glenn Perry trimmed torn cartilage during the procedure.

There was no timetable for May's return, but he's expected to need at least eight weeks to recover -- and probably won't be pushed to return to the court.

"We want Sean to get healthy and get everything taken care of," Bobcats coach Bernie Bickerstaff said. "We want him to take his time. There will be no rush for him to come back -- he is too important to our franchise."

Bobcats coach Bernie Bickerstaff tried to squash rumors that teams are trying to trade for Knight.

"I haven't had any conversations with anyone, so expending vocal energy on that is of no significance," he said, adding that the second-year team is still too thin to deal away its starting point guard.

Things were looking good for the Charlotte Bobcats: Emeka Okafor returned after an eight-game absence and Brevin Knight's back was feeling better.

Against an undermanned Houston Rockets team, it should have been an easy win.

Instead, the Bobcats had to claw their way through two overtimes -- losing Okafor and Knight to more injuries along the way -- before finally pulling out a 111-106 win over Houston on Tuesday night.

"Our guys just kept fighting, after one overtime, two overtimes," coach Bernie Bickerstaff said. "They just kept fighting and found a way."

Raymond Felton made a running jumper with 20 seconds to play in the second overtime, then hit a pair of free throws to seal the Bobcats' win.

But Okafor, who had been sidelined with a sprained ankle, re-injured himself late in the second overtime when he stepped on someone's foot. He had to be helped from the court, his right shoe off, and was on crutches after the game.

He won't travel to Wednesday night's game in Toronto, instead staying behind for an MRI.

"I'm kind of worried," said Okafor, who had 21 points before he was hurt. "I'm not in too much pain, but I also can't really move it."