"He believes he can win this tournament" - Andy Roddick on Nick Kyrgios

Nick Kyrgios ousted number one seed and defending champion Daniil Medvedev at the US Open and former champion Andy Roddick was impressed.

Roddick is a former champion of this event and former number one so he knows what it takes to win an event like this. Kyrgios is hoping to do that after coming close earlier this year at Wimbledon. The American was impressed by Kyrgios and his display in the match taking to social media network Twitter to voice his thoughts.

He noted the focus of Kyrgios and just how much self-belief he has writing:

"As focused as I’ve seen NK early in a match. He believes he can win this tournament."

A fan asked him what would it take for him to be on top of tennis with Roddick simply saying:

"Discipline, fitness, and ability to accept the grind as it comes"