Tony Stewart still faces a long and difficult road to recovery, but roughly 48 hours after undergoing spinal stabilization surgery, informed sources say the Indiana native is progressing well in his rehabilitation.

Stewart suffered a burst fracture of his L1 vertebra Sunday in a sand buggy incident in the California desert. He was transported to a local hospital and evaluated, before being flown to North Carolina facility Tuesday for further evaluation.

The three-time Sprint Cup Series champion underwent surgery Wednesday to remove dangerous bone fragments from the area of the fracture and stabilize the affected vertebra. While many victims of burst fractures are forced to wear a stabilizing brace for 2-3 months post-op, the procedure performed on Stewart reportedly will not require a brace.

In fact, sources say Stewart was on his feet and walking by Friday. Sources close to the situation say that on the advice of his doctors, Stewart and his team have set a tentative return date of May 21, the day of the 2016 NASCAR Sprint All-Star Race at Charlotte Motor Speedway.

Stewart is highly unlikely to return earlier than that, and his timeline for return could easily be pushed back, depending on the success of his rehabilitation program.