Federer wins on impossibly close review

World No.2 Roger Federer has kicked off Switzerland's bid to progress in the Hopman Cup with a straight-sets victory over Russian youngster Karen Khachanov on Tuesday night.

The Swiss great was broken in the first game of the match but fought back to take the opening set and the match 6-3 7-6 (10-8) in 77 minutes.

Federer took out the win on one of the tightest reviews you will see, with Khachanov praying his ball had touched the line.

Watch the moment in the video player above

Both players produced some marvellous tennis inside Perth Arena, while a slight delay in an earlier review saw an impatient Federer get a chuckle out of the crowd.

"I can't take it, it's too nerve-wracking," he said.

Federer started his Hopman Cup campaign with a straight sets win over Japan's Yuichi Sugita.

And although he started slowly against Khachanov, he quickly bounced back to win the opening set in 29 minutes.

The second set was an entertaining arm wrestle as both players produced powerful service games.

But Federer finally cracked the Russian in an epic tiebreak, saving a set point to secure the win on his third match point, courtesy of that successful challenge.

with AAP