BASEL, Switzerland (AP)Top-ranked Carlos Alcaraz will face No. 9 Felix Auger-Aliassime in the Swiss Indoors semifinals after both advanced in straight sets Friday.

Alcaraz, who won the U.S. Open last month, clinched a 6-3, 6-4 win against fellow Spaniard Pablo Carreno Busta with a service winner.

”It is difficult to play against a friend like Pablo,” the 19-year-old Alcaraz said in a post-match interview on court. ”Every day we go and have dinner, lunch together.”

Auger-Aliassime hit 31 winners and made just four unforced errors in a 6-2, 6-3 win over Alexander Bublik.

The 22-year-old Canadian is seeking a third straight title – after wins in Florence, Italy and Antwerp, Belgium this month – and has not faced a break point on his serve in three matches at Basel.

Auger-Aliassime landed in Alcaraz’s half of the draw as the third-seeded player in Basel. Second-seeded Casper Ruud lost in the first round to three-time Grand Slam champion Stan Wawrinka, who lost his quarterfinal 7-5, 7-6 (5) to sixth-seeded Roberto Bautista Agut.

A second 19-year-old, Holger Rune, took his place in the semifinals by beating unseeded Arthur Rinderknech 7-6 (0), 6-2. The 25th-ranked Rune is aiming for back-to-back titles after winning last weekend in Stockholm.

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