Roger Federer survived a huge scare against unseeded Thai Paradorn Srichaphan to reach the Swiss Indoors final on Saturday.
Federer, chasing his first hometown title, had to twice fight back from a mini-break down in the decisive third set tiebreak before eventually winning 6-4, 3-6, 7-6.
Losing the first set on a single break of serve, the world number 54 was clearly the better player in the second set, bamboozling Federer with solid serving and a string of winners.
Bidding to become only the third man this season to beat the nine-times Grand Slam champion, Paradorn led 5-3 in the third set tiebreak before Federer finally dug his way out of trouble by winning the last four points of the match.
The Basel-born world number one now meets third seed Fernando Gonzalez in Sunday's final after the Chilean beat Federer's compatriot Stanislas Wawrinka 6-4, 6-4.
LUCK NEEDED
"It was unbelievable," Federer said of his near-collapse.
"I've played him a few times now so I knew he was a good player but I definitely needed a bit of luck today."
While Federer has yet to win the Basel title in six previous attempts, Gonzalez is the defending champion and on a good run of form with Sunday's final being his third in a row.
However, last week's Madrid final saw the world number seven comprehensively outgunned by Federer who won the Masters Series event 7-5, 6-1, 6-0.
Federer also boasts a perfect record against Gonzalez, having won their previous eight meetings.
"I'll need to be at my best against him because when you play Federer you maybe get one good chance when other players might give you ten," said Gonzalez.
"I will just have to use my best weapons, my serve and my forehand, and try to get forward as much as possible."