The Tennis was actually scheduled on the ABC affiliate, and was being broadcast there. Then, when it became imminent that the POTUS was about to make an announcement about our involvement in the Libyan situation, the tennis was moved to ESPN classic to make room for the POTUS to make his public announcement.
I didn't like it either, but not everyone has ESPN classic, and most DO have regular broadcast channels, so a regular broadcast channel was made available, and a LIVE event was moved and pre empted a taped event.