Federer, yet to lose a set in the tournament, was broken for the first time in the match at the tail end of the third set but recovered to secure a ffith break of serve to set up a first career meeting with unseeded Hungarian Marton Fucsovics, who defeated Argentine Nicolas Kicker.
The 36-year-old will next play Richard Gasquet on Saturday and boasts an impressive record against the 29th seed having beaten the Frenchman 16 of the 18 times they've played.
Speaking at a news conference on Thursday, the American actor and comedian said he felt the 19-time grand slam champion was scared of him.
"I honestly can't complain - the ATP is doing a nice job and there's a lot of physios and communication going on from officials towards us players".
The world No. 2 beat Jan-Lennard Struff in straight sets in the final match on the Rod Laver Arena, after a blistering hot day at the first Grand Slam of 2018.
"If I can get a first serve in, it's heaven". In the past ten matches, Struff has won five matches and lost five matches. That shotmaking ability will be key here if Struff hopes to pull off an upset.
Next up is in-form 2016 Australian Open champion Angelique Kerber, who beat Donna Vekic in two easy sets as she starts to rediscover her best again after a miserable past year.
Argentine Juan Martin del Potro, World No.10 prevailed over Karen Khachanov of Russian Federation 6-4, 7-6 (7-4), 6-7 (0-7), 6-4 securing a place in the Australian Open third round for the first time since 2013. Struff has split his last eight matches on hard court.
"It was obvious we both suffered on the court today".
As reported by the Daily Telegraph, Federer was very complimentary of his opponent after the match.
The 2014 champion, seeded ninth, only made a decision to play in Melbourne on the eve of the tournament and was well below his best as he lost 6-2 6-1 6-4 to Tennys Sandgren of the USA. There's not betting against Federer until he provides a reason not to bet against him.
In typical Federer fashion, he broke back immediately, sealing the fifth game of the set with a sumptuous backhand pass and then held for 3-3.