All I know is Pierce said he heard a pop, which is the last thing I wanted to hear. Not trying to be a pessimist, but that is something people hear / sense when they tear a knee ligament. Of course, even if it is a tear, depending on the type and given the strength of his legs, he may be able to gut it out for the series anyway. . . .
But here's hoping its just a treatable sprain and the captain is okay. Lord knows the Celtics need him. And, regardless of the outcome of the series, it would be quite sad if he were unable to participate.
Anyway, I would imagine that most people, like myself, are so pumped right now that they arent really concerned / are presuming he is okay because he came back in the game.