CoCo Vandeweghe says Alexander Zverev lacks one key thing‎

Following his defeat to Jannik Sinner in the Madrid Open final, Alexander Zverev stated that he sees himself on par with Carlos Alcaraz and Novak Djokovic. Zverev suggested there were three groups: 1) Sinner, 2) Himself, Alcaraz, and Novak Djokovic, and 3) The rest of the field.