Synonyms : baffle board

Example : This beats me!.
Got me--I don't know the answer!.
A vexing problem.
This question really stuck me.

Synonyms : amaze, beat, bewilder, dumbfound, flummox, get, gravel, mystify, nonplus, perplex, pose, puzzle, stick, stupefy, vex

Example : What ultimately frustrated every challenger was Ruth's amazing September surge.
Foil your opponent.

Synonyms : bilk, cross, foil, frustrate, queer, scotch, spoil, thwart

Synonyms : regulate