"He's the only guy that can even compare to the Big 3" - Andy Roddick has high praise for Kyrgios

Andy Roddick believes Nick Kyrgios is at par with the Big 3 on physical ability but warned that the Aussie's body is unreliable in sustaining itself for several matches.

Kyrgios stunned World No.1 Daniil Medvedev in the second round of the National Bank Open (Rogers Cup) on Wednesday, winning 6-7(1) 6-4 6-2. With this win, the Aussie had won 13 out of his last 15 singles matches on tour.

The two matches the mercurial Aussie did not win include his Wimbledon defeat against Novak Djokovic and the walkover he received from Rafael Nadal at the All England Club.

Kyrgios would go on to defeat countryman Alex De Minaur in straight sets in the Round of 16 in Montreal. Speaking about that match on Tennis Channel, Andy Roddick highlighted how the Wimbledon runner-up is currently enjoying the form of his life.

"Listen, if we're just going on balls and strikes here, Kyrgios is playing at a completely other level," Roddick said. "He has options, right. We are talking about is he gonna come in non-stop, is he gonna stay back."

The former World No.1 stated Kyrgios had the tools to down De Minaur and heaped special praise on the 27-year-old's physicality. That said, Roddick pointed out that Kyrgios' body can collapse at any minute, given he is not used to playing this many matches in a row.

"So whatever De Minaur does, I think Kyrgios is able to adjust - he has that amount of variety I think," he said. "Just based on physical ability I think he's the only guy that can even compare to the Big 3 of this generation but I still don't know is it gonna explode - he's played a lot of tennis. Is it just a time bomb?"