I guess I will take the lens to repair shop like I said I would. The malfunction of the lens might be caused by moisture, as the swimming pool was very hot and humid. I will give the lens a test again later to see if it rights itself again or not. In any case, this is very frustrating, as it is the main lens I use for my kids' sporting events. I used the EF 135mm f2 for the whole event today, but it just did not have enough reach. Hopefully, the lens can be fixed.
Dillon the Piano Man playing accompaniment for the school choir - 1D III & EF 85mm f1.2.