Roger Federer will get a chance to claim his 99th ATP Tour level title in the final of the Swiss Indoors against unfancied qualifier Marius Copil.

On his home court in Basel, Federer dismantled Russian Daniil Medvedev 6-1 6-4 in their semi-final.

"I'm very happy. I think it was my best performance this week," Federer said.

"I'm starting to really get to understand the conditions and it was consistent, my most consistent match by far.

"The results show it as well, so I'm very happy."

The eight-time champion and title holder was competing in his 12th straight Swiss Indoors semi-final of 15 in total, having lost only once before.

Apart from his absence in 2016, Federer has reached every final of the event since 2006.

The 37-year-old is second on the all-time singles titles list, trailing only Jimmy Connors who won 109 times.

On Sunday, Federer will meet Copil in the decider after the world No. 93 stunned German second seed Alexander Zverev 6-3 6-7 (6-8) 6-4.

In 150 tour-level finals, Federer has never lost to someone ranked as low as Copil, who also beat world No.6 Marin Cilic en route to his second ATP final.

"I watched some against Cilic, he played great. Saw some against Zverev, he played great, too. He plays Federer, he plays great? I'm not sure. But anyway, I'm excited," Federer said.

Romanian Copil sent down 26 aces and won 85 per cent of his first serve points against Zverev, including 17 of 18 in the final set, as he ground out the victory in two hours and 30 minutes.

"It's been an unbelievable week for me so far," 28-year-old Copil said.

"Before coming here, I was fighting and struggling to have the (ranking) points to finish in the top 100, and that was in my mind.

"I was trying to win one or two matches here just to stay there but now, being in the final, it's an unbelievable achievement for me."

Copil is the first qualifier to compete for the Basel title since Cypriot Marcos Baghdatis in 2005 and the lowest-ranked player since Patrick McEnroe, who was ranked at 100 in 1994.

If Copil pulls off an upset win against Federer he will enter the top-50 and smash his previous best ranking of 73.