EAST RUTHERFORD, New Jersey (AFP) - New Jersey Nets forward Yi Jianlian has started rehabilitation on a sprained right knee ligament but there is no timetable for the Chinese 7-footer's return, the NBA club said on Tuesday.

MRI results showed the Nets the extent of Yi's injury, suffered in a 79-68 loss at Charlotte on Monday.

Yi, 22, came to the Nets from Milwaukee in a trade last year. He played on the 2004 and 2008 Chinese Olympic teams.

Bobcats forward Gerald Wallace fell and rolled into Yi's leg halfway into the third quarter, sending the Asian star to the floor. He was helped off the court without putting weight upon his injured leg.

"I fell on my knee and kind of twisted it a little bit," Yi said.

Yi scored four points and grabbed six rebounds for the Nets, who are off to an 0-4 start to the new NBA camapign.