garbage time (gar'-bij tym) noun. The time remaining in a basketball game when the contest has been effectively decided by a lopsided score, the coaches empty their respective benches, and the level of play drops to unwatchable levels.

Usage example: The Suns just annihilated the Pacers last night. It was garbage time by the start of the second half.

garbage time
Yep. That just about sums it up.