Alcaraz, the tournament favorite on paper as the number one seed, deservedly lost to Auger-Aliassime.
The Canadian was the better player, taking three of his eight break chances and holding his serve throughout the game.
In addition, the 22-year-old scored a whole series of so-called free points with nine aces, while Alcaraz did not score an ace.
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After an hour and 21 minutes, Auger-Aliassime ended the game in his favour.
Basel, on the other hand, was an improvement, even though Auger-Aliassime lost after three wins. The Canadian is now aiming for his fourth title of the season in the final after Rotterdam, Florence and Antwerp.
Auger-Aliassime: “A fantastic week”
“So far it’s been almost perfect. I’ve served fantastically and haven’t been broken once. There’s still a match to play, but it’s been a fantastic week,” said Auger-Aliassime. “It’s a great win, I’m really happy with my level and I hope to see it through to the end.”
Octopus in top form: Endurance runner Alcaraz makes Carreño Busta despair
ATP Vienna
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ATP Basel
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