Greg OdenGreg Oden participated in five-on-five drills with the Miami Heat on Monday — his first NBA practice scrimmage in almost four years. The scrimmage appears to have taken a toll on Oden, as he sat out Tuesday’s practice with swelling in his knee (the team called it a precautionary measure), as well as Tuesday night’s pre-season game against the Washington Wizards. As the Miami Herald‘s Joseph Goodman reports, Oden still iced his knees Tuesday night.

It didn’t help. The swelling in Oden’s knee flared up again Wednesday, thus relegating the big man to spectator status for a second consecutive practice.

Now, we can’t call it a major setback, as Oden is unaccustomed to the movement and pace of even a practice scrimmage, and there were likely to be some lingering effects (similar to Derrick Rose sitting out a pre-season game). Unfortunately, at this point, we can’t write the words “Oden” and “left knee” (either knee, really) in the same sentence without visions of worst-case scenarios dancing in our heads.