Denard Span. (AP Photo/Alex Brandon)

Denard Span is scheduled to begin his minor league rehab assignment at Class A Hagerstown on Thursday night. The Nationals expect Span to get three at-bats in his first rehab game and increase the workload to four at-bats in a second rehab game.

That Span is playing in a rehab game presumably means he passed his evaluation on Wednesday. The center fielder flew back to Washington ahead of the Nationals to be evaluated by a doctor here.

Span suffered a mild concussion on Friday and, along with feeling better, had ramped up his physical activity in recent days, including batting practice and running the bases. He took a concussion test on Tuesday and scored higher than his baseline score from years ago.

If all goes well, Span could rejoin the Nationals on Saturday, the first day he is eligible to come off the seven-day concussion disabled list. Span and the Nationals want to be cautious because the outfielder suffered a concussion that limited him to only 70 games in 2011.

Span suffered the most recent concussion on Friday when he collided with Dan Uggla rounding first base in the eighth inning.