You've probably fallen for this costly psychological trap without realizing it. Learn why we can't quit failing ventures—and how to escape.

Aryna Sabalenka showed nerves of steel and champion's resolve to defeat Elena Rybakina in their Berlin Open quarter-final on ...

Alexander Zverev sprints off court to vomit mid-match but recovers to beat Italy's Flavio Cobolli at the Halle Open.