Millman hopes to out-fox Federer without 'The Fox'

Dilemma for Australia's John Millman

John Millman will face his personal hero Roger Federer for a place in the US Open quarter-finals but will tackle the greatest challenge in tennis without his biggest inspiration, his father Ron, aka 'The Fox'.

Millman, 29, reached his first Grand Slam fourth round on Saturday by seeing off Mikhail Kukushkin of Kazakhstan 6-4, 4-6, 6-1, 6-3.

Next up will be 20-time major winner and five-time US Open champion Federer on Arthur Ashe Stadium on Monday.

However, Millman senior won't be there.

They haven't had a falling out -- it's just that in the madness of New York, Ron may not make it to the stadium out in Queens, a traffic jam or a subway train ride from the players' hotels in Manhattan.

"If he gets lost in London, I thought if I flew him over here, I mean, this is a big place, you know. Manhattan is crazy," said Brisbane native Millman.

"I've even gotten on the wrong train in Manhattan. I reckon my dad, he'd end up in New Jersey.

"He'd jump on a plane at any opportunity but he'll probably get on the wrong flight and wind up on the other side of the world."

Millman made a reluctant social media star of his father after 'The Fox' lost his sense of direction on the gentle, quiet streets in and around Wimbledon this year.

Millman senior, however, made up for it when he had to make a mad dash from the All England Club to frantically search for underwear after his son's playing attire fell foul of Wimbledon's famous all-white dress code.

The Australian lost his only previous meeting with Federer at Brisbane in 2015 but insists he will not be over-awed by Monday's occasion.

He got a chance to hit with Andy Murray on Ashe before the US Open got underway and has trained with Federer in Europe.

"I've got a lot of respect for Roger. I've got a lot of respect for his team.

"He's got an aura about him. Definitely a player I've looked up to throughout my career.

"But I have never been a fan of playing anyone's reputation. I want to start off at 0-All and not already being behind the 8 Ball.

"If you do that, I think you can get bogged down and you're in a bit of trouble."

- Biggest moment -

World number 55 Millman has endured a rollercoaster career in getting to this stage, undergoing two surgeries on his shoulder and one on his groin.

As a result of his injury toils, his ranking slumped to 1,101 in August 2014 but recovered to 71 just 12 months later.

After a groin operation, he was slipping again with his ranking at 235 in August last year.

However, he has enjoyed a solid 2018, earning his first top 15 win over Lucas Pouille in Budapest on his way to a maiden ATP final where he finished runner-up.

Last month, he reached a career-high ranking of 49.

"This is the biggest moment of my career," said Millman.

"It's been a bumpy road. I have had three surgeries and every time I had extreme doubts over whether I would get back.

"But I have got great people around me who lift me up when I'm feeling sorry for myself."