mop the floor up with
mop the floor up with (one)
1. To easily and thoroughly defeat one in a competition or contest. Primarily heard in US. Although he wasn't favored to win the race, Jack really mopped the floor up with the competition. Everyone was impressed the underdog team made it to the finals, but the returning champions mopped the floor up with them.
2. To physically beat or thrash one to the point of serious injury or incapacitation. Primarily heard in US. Tom got into a fight with some dude at the bar, but the other guy mopped the floor up with him.
mop the floor up with someone
to overwhelm and physically subdue someone; to beat someone. Stop talking like that, or I'll mop the floor up with you! Did you hear that? He threatened to mop up the floor with me!