Take the wind out of one's sails

From Fresh Dictionary

English

Verb

to take the wind out of one's sails

1. ((idiomatic{{#if:|, {{{2}}}{{#if:|, {{{3}}}{{#if:|, {{{4}}}{{#if:|, {{{5}}}{{#if:|, {{{6}}}{{#if:|, {{{7}}}{{#if:|, {{{8}}}{{#if:|, {{{9}}}}}}}}}}}}}}}}}}})) To discourage someone or to cause someone to lose incentive.

   It really took the wind out of his sails to know that even if he won the match, he could only place second in the tournament.