Roger Federer couldn't help but crack a cheeky smile after being aced by Japanese player Naomi Osaka.

Federer and Swiss teammate Belinda Bencic were too good for Osaka and Yuichi Sugita in the opening tie of the Hopman Cup on Saturday night, sweeping to a 3-0 victory.

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However the Swiss didn't have it all their own way, with Osaka winning the biggest cheer of the night when she managed to ace the legendary Federer.

Osaka unleashed a brilliant serve out wide that Federer couldn't reach, with the Japanese player throwing her arms into the air in triumph.

Brilliant moment. Image: Channel 7 More

Federer couldn't help but smile at her reaction, although there was a hint of sheepishness on his face.

The World No.2 gave his return to the court a big tick after powering past Sugita 6-4 6-3 at Perth Arena.

Federer was forced to save a break point in his first game, and shanked a forehand into the crowd during the opening set before breaking world No.40 Sugita in the fifth game.

From there it was all one-way traffic as the 19-time grand slam winner wrapped the match up in 66 minutes.

Switzerland secured the tie win after Belinda Bencic beat Naomi Osaka 7-5 6-3 in 91 minutes in the women's singles rubber.

Despite Federer's easy singles win, he was rusty at times.

The 36-year-old said it was nice to dust off the cobwebs in his first tournament since playing in the ATP World Tour Finals in mid-November.

At this time last year, Federer was entering the unknown after spending six months out with a knee injury.

But after winning two grand slams including the Australian Open in a wildly successful 2017 campaign, Federer said he felt more at ease in his Hopman Cup opener compared to the previous year.

"This year I feel much more in a rhythm," Federer said.

"You get to break point or the moment where you have to serve the first time of the year, and it's a normal thing.

"Whereas last year, I was like, 'Ooh, I hope I'm going to be able to hit my first serves, and I hope it's going to work out as much as it did in the practice'.

"I think all those question marks aren't really there this time around, which is a nice thing."

with AAP