I think everyone thought that ball was gone, based on the swing and location of the hanging curve. I don't think any hitter would have ran down the line full speed after that. Carlos thought it was gone too, as he threw the ball into the SS, rather than to 2B, if he thought he had a play, or to 3B, if he did not think he did. The fact the SS was where he was tells me he never moved either, as he should have been in between the LF and either 2B or 3B. It fooled everyone, Billy must have got the top half of the ball just a bit, rather than the lift it appeared he had gotten.