BASEL, Switzerland — Roger Federer was tested before beating 28th-ranked Adrian Mannarino, 4-6, 6-1, 6-3, in the Swiss Indoors quarterfinals on Friday.
The top-seeded Swiss saved two break points when trailing, 3-2, in the decisive set, including with a backhand half-volley winner from the baseline.
Federer never gave the French left-hander another chance and clinched his first match point on Mannarino's serve with another in a series of backhand winners.
A finalist in his last 10 appearances at his hometown event in Basel, Federer will play either David Goffin of Belgium, who defeated Jack Sock of the US, 7-6 (6), 6-3.
Marin Cilic and Juan Martin del Potro, both former US Open winners, will face each other in the other semifinal after also being pushed to three-set wins.
Second-seeded Cilic was on court for more than three hours to beat 100th-ranked qualifier Marton Fucsovics of Hungary, 7-6 (3), 5-7, 7-6 (4).
Cilic, the defending champion at Basel, clinched the quarterfinal with a delicate sliced backhand volley for a winner.
Fourth-seeded Del Potro needed exactly two hours to win 6-2, 2-6, 6-4 against sixth-seeded Roberto Bautista Agut of Spain.
Del Potro, who won back-to-back Basel titles in 2012 and '13 beating Federer in the final, will qualify for the ATP Finals in London if he wins the title on Sunday.