The amazing Roger Federer will embark on his 21st professional season when he leads Switzerland in the mixed teams Hopman Cup starting in Perth on Saturday.

The 36-year-old Swiss is coming off an extraordinary year where he took his majors tally to 19, with a fifth Australian Open title and a record eighth Wimbledon.

Federer finished the year at number two in the world behind Spanish rival Rafael Nadal, having started at 16, after a season-leading seven titles, including three Masters at Indian Wells, Miami and Shanghai.

It was a sensational season by any standards, but especially as Federer has been playing professional tennis since 1998 -- a year when Bill Clinton was president of the United States, and James Cameron's "Titanic" won 11 Oscars.

Federer will again partner Belinda Bencic at the Hopman Cup, his only event before launching his Australian Open title defence on January 15.

"It's totally different this time around," said Federer, whose appearance at the previous edition of the Hopman Cup followed a rare six-month absence as he recovered from injury.

"I had a great off-season. I mean, I did have a good off-season too last year but I just wasn't sure what to expect.

"Now expectations are higher but at the same time I try to remind myself, 'Just don't think it's normal and realistic to aim for the same things I did this year in 2017'.

"I've got to try and keep it cool, try my best and see what happens -- but the preparation's been good so far."

- Relaxed setting -

Federer and Bencic teamed for the first time at last year's Hopman Cup, only just missing out on sending Switzerland into the final.

Bencic missed five months of 2017 after undergoing wrist surgery.

"She had a tough year after that so it's nice to see her back in shape as well," Federer said.

Three guaranteed matches in the Hopman Cup's round robin stages are a perfect preparation for Federer, who also thrives in the relaxed setting of Perth with his family in tow.

He will be up against American world number eight Jack Sock in his pool, while he could face Germany's world number four Alexander Zverev playing in the opposite side of the draw in the final.

While Federer is a tour veteran, Zverev's coming-of-age campaign saw him win five titles and become one of just four men to beat the Swiss great this year, in the Montreal final.

His progress up the rankings has marked him out as the most likely of the current crop of youngsters to translate his talent into Grand Slam titles.

The tall German had a roller-coaster year at the Slams -- a last-16 spot at Wimbledon, but also a first-round loss in Paris, a second-round exit in New York and a third-round defeat to Nadal in Australia.

Zverev will partner former world number one Angelique Kerber, and they kick off their Hopman Cup campaign against Belgium's David Goffin and Elise Mertens.

Vasek Pospisil and Eugenie Bouchard are in Canada's team along with Germany, Belgium and Australia in Pool A.

Russia will be represented by Karen Khachanov and Anastasia Pavlyuchenkova, while Yuichi Sugita and Naomi Osaka are playing for Japan both in Pool B.