Knock spots off somebody/something
Definition 1 of 1
Pro Tip 1/3Colloquial Charm
Used in informal situations among friends, not in formal writing or speeches. 
Your homemade pie knocks spots off the bakery's version.
Pro Tip 2/3Competitive Edge
Often used when comparing and emphasizing one's superiority over others, especially in performance. 
This software knocks spots off the alternatives we tried.
Pro Tip 3/3Not Literal
The phrase is metaphorical, meaning there aren't actual spots being knocked off. 
In last night's game, our team knocked spots off them!