By Sudipto Ganguly

MELBOURNE (Reuters) - Roger Federer regained control after a slow start against Hungarian Marton Fucsovics to march into the quarter-finals of the Australian Open with a 4-6 6-1 6-2 6-2 win on a chilly evening at the Rod Laver Arena on Sunday.

The six-time Australian Open winner, who was two points from defeat against John Millman in his previous round, looked rusty in the opening set against Fucsovics in a repeat of their fourth-round clash here in 2018.

"The morning after Johnny's match and this morning I lay in bed for an hour thinking, 'when are we going to stand up? Okay 1-2-3, huh, and how do I feel?" he laughed, referring to his 4-6 7-6(2) 6-4 4-6 7-6(8) win over Millman.

"I was able to recover; I'm sure I'm going to feel better every day that goes by after that match."

Fucsovics had not won a set against Federer in their previous two meetings but wiped that off his record after getting the only break in the seventh game of the opener when the Swiss committed three straight unforced errors.

"It was a tough start, I thought that Marton played clean, I struggled with the (after-effects) from the Millman match," said the 38-year-old Federer, who hit 44 winners as opposed to 36 unforced errors against Fucsovics.

"He gave me a beat-down from the baseline so maybe he took my confidence away a little bit. It just took some time, I was looking to maybe mix it up a little bit more. It gets pretty slow in the night time, especially when it's cool like this."

The 20-times Grand Slam winner shifted up a gear in the second set and broke Fucsovics's serve twice to level the match.

Federer maintained his intensity in the third and a couple of early breaks gave him a 4-0 lead while he broke Fucsovics twice more in the fourth set to complete the victory.

With the cool conditions and a bit of breeze both players struggled with their first serves, with Fucsovics, who has now lost all six of his matches against top-five opponents, getting in 47% of his.

"It's frosty," joked Federer. "It's not that cold, it's fresh. We know how it can be in Australia this time of year. It's better this way. I don't know who wants it incredibly hot."

The third-seeded Federer will now face American Tennys Sandgren, who defeated No. 12 seed Fabio Fognini 7-6(5) 7-5 6-7(2) 6-4 earlier on Sunday.

Federer was visibly in a good mood after reaching the Australian Open quarter-finals for the 15th time and engaged in some light banter about his next opponent's unusual first name.

"He was not going to be a baseball player, that's for sure. I'm looking forward to it," he said, before breaking into laughter. "I've played a lot of tennis in my life but never against Tennys."

(Reporting by Sudipto Ganguly; editing by Clare Fallon)