For four months, Mike Rucker has spent up to four hours a day rehabbing his knee. Determined to return to the Panthers despite his age and the seriousness of his injury, the 32-year-old is grinding away, hoping to be ready to practice before the end of training camp. "It's been tough because there hasn't been an offseason," Rucker said Friday. "The day it happened, we started rehabbing the next day. That's part of the emotions that you go through when you have an injury like that because you know what is ahead of you."