Roger Federer fired an ominous warning to his rivals ahead of the Australian Open, stating he has found his groove quicker at the Hopman Cup than he did 12 months ago.

The Swiss maestro enjoyed a stunning resurgence in the 2017 season, taking his career grand slam tally to 19 with wins in Melbourne and Wimbledon.

Federer started the new season in impressive form at the Hopman Cup with a dominant 6-4 6-3 beating of Japan's Yuichi Sugita.

Federer, who will turn 37 in 2018, believes he is quickly finding best rhythm in Perth.

"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, 'Oh, 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."

Federer added that his condition feels good, saying: "I'm just very happy I was able to have a good level and stay calm under pressure.

"I had some good moments moving forward [to the net] and playing up in the court. That's how I want to play for the year. I think it was a great start."

There was another Swiss victory in Group B as Belinda Bencic saw off Naomi Osaka 7-5 6-3, and she and Federer made it a clean sweep over Japan with a come-from-behind win in mixed doubles.

In Group A, Jack Sock and CoCo Vandeweghe defeated Karen Khachanov and Anastasia Pavlyuchenkova for the United States, but the Russia duo earned a measure of revenge in the mixed doubles.