Wiktionary
lick the pants off
alt. (context transitive idiomatic English) To thoroughly and decisively defeat someone, either in a physical fight or, figuratively, in a competition. vb. (context transitive idiomatic English) To thoroughly and decisively defeat someone, either in a physical fight or, figuratively, in a competition.
Usage examples of "lick the pants off".
He played chess very well and joined the chess club in Aprelevka where he proceeded to lick the pants off his elders and betters.