Home hero Roger Federer won his 32nd match from his last 33 played at the Swiss Indoors on Friday, reaching the semi-finals in emphatic fashion over Benoit Paire, 6-2, 6-2.
The 23-year-old French challenger knew he was in for the match of his life against the five-time tournament winner who was born in Basel.
The force of the world number one and top seed was on full display in his 54-minute quarter-final rout of the outsider, a victory studded with seven aces and four breaks of serve.
Federer will Saturday play another French opponent when he takes on fellow veteran Paul-Henri Mathieu, who reached his second semi-final since coming back in late January after a year away with a knee injury.
Mathieu claimed his final-four spot with a 7-6 (7/2), 7-6 (7/4) win over Bulgarian Grigor Dimitrov.
Second seed Juan Martin del Potro struggled into the semi-finals by beating South African Kevin Anderson 3-6, 7-6 (7/3), 6-2, a day after qualifying for the year-ending ATP World Tour Finals.
The Argentine will take a 4-1 lead into his match with French third seed Richard Gasquet, who kept alive his bid to secure one of the two remaining places in the eight-man event in London with a 6-2, 7-6 (7/5) defeat of sixth seed Mikhail Youzhny.
Federer suffered his only recent defeat in Basel in 2009 when he lost the final to Novak Djokovic.
But the Swiss was taking no chances in front of his sold-out public, sweeping the opening set against Paire in 29 minutes with two breaks.
The second set was equally brief as Federer moved within two wins of his seventh trophy of the season.
He broke Paire's first two service games and sent down over a pair aces for a 5-1 lead before closing it out.
"It was a good match for me and I'm pleased to be back in the semi-finals," said the world number one.
"It cannot have been easy for him playing a top 10 player. I had to play aggressive, but by the fourth game of the match, I knew what I had to do.
"I'm looking forward to playing Paul-Henri, he's from my generation. It's good to see him back as well after his knee problems. I'm looking forward to the match."
Del Potro, playing only his second event since coming back from a month off to heal a left wrist problem, was pleased to get past Anderson, who fired 20 aces in defeat.
"It was tough to find my way into the match, he played well at the start," said Del Potro.
"I was lucky to stay in the match in the tiebreaker. But the third set was a lot easier than the first two. I played really well then, broke him twice and got some confidence.
"I stayed calm in the third set, that was the key to this match, trying to remain calm all the time on court."
Del Potro said he is keeping his mind on the task at hand.
"I'm not thinking about London yet, only about trying to play a couple of more matches here," he explained.
"I'd love to be in the final, maybe against Federer. But I need to play better tomorrow if I want to win."
Gasquet is also seeking one of two remaining spots in the London field, trailing three rivals as he stands adrift of compatriot Jo-Wilfried Tsonga, Serb Janko Tipsarevic and Spain's Nicolas Almagro.
Of the three, Tsonga and Tipsarevic quit first-round matches due to injuries in Valencia while Almagro reached the quarter-finals but lost to David Ferrer on Friday.