Verbs

(v)thwart, queer, spoil, scotch, foil, cross, frustrate, baffle, bilkhinder or prevent (the efforts, plans, or desires) of“What ultimately frustrated every challenger was Ruth's amazing September surge”, “foil your opponent”
(v)torment, rag, bedevil, crucify, dun, frustratetreat cruelly“The children tormented the stuttering teacher”