Germany's Alexander Zverev will face world number one Novak Djokovic in the ATP Finals last four after a straight-set win over Poland's Hubert Hurkacz.
Third seed Zverev, who won the title in 2018, was rarely troubled by an off-colour Hurkacz in a 6-2 6-4 victory.
Zverev secured second place in his group as a result, finishing behind defending champion Daniil Medvedev.
Medvedev awaits the winner of Friday's match between fellow Russian Andrey Rublev and Norway's Casper Ruud.
Top seed Djokovic, who is aiming for a record-equalling sixth title, qualified as group winner with opening wins against Rublev and Ruud in Turin.
The 34-year-old Serb plays British number one Cameron Norrie, who cannot qualify after losing to Ruud on his tournament debut, in his final round-robin match.