The world No 2 brushed aside Marton Fucsovics yesterday to book his place in the last eight and he is still yet to drop a set in the tournament.
Jan-Lennard Struff, Richard Gasquet and Aljaz Bedene have all been unable to take Federer past three sets with Fucsovics his latest victim.
And his route to the final became slightly easier when Novak Djokovic suffered a shock defeat to Hyeon Chung.
Federer will first have to overcome Tomas Berdych, who he beat en route to his 2017 Australian Open crown.
But the 36-year-old remains quietly confident he can go all the way.
“You don’t have to say it out loud sometimes because it is not a walk in the park,” Federer told Eurosport.
“It’s not easy just to come here easy and brush aside seven opponents, it just doesn’t happen and it’s not realistic.
“That’s why I like to first set a goal first of getting to the quarters, I’m there now and this is where the second tournament starts in someways.
“Now it’s like three matches and you can see the light at the end of the tunnel and you feel like you can go all out.
“In the beginning you just don’t know. You might have another five or six sets where you have to be ready for mentally and physically.
“As a defending champion you always want to come back and defend but I said before that I don’t think a 36 year old should be, and I’m not joking, the favourite.”