Key Points

Zverev went past Shelton with a scoreline of 6-2, 6-2, needing just an hour and 17 minutes to end the American's nine-match winning streak and secure his fourth successive semifinal appearance in the past four tournaments.

During the second set, Zverev struggled with his health and breathing and called for a doctor.

Speaking after the match, Zverev, the 2021 champion in Cincinnati said as quoted by ATP's official website, "Right now I am not feeling too great. I am not sure what happened. I came out today and probably felt the best I have felt in a few months. Was feeling the ball incredibly well from both sides. In the first set I started feeling not so great and it got progressively worse. But I am in the semi-finals and I will do everything I can to be 100 per cent tomorrow."

After failing to win his first six matches here in this competition, Zverev marked a brilliant turnaround with 16 wins in his next 18 outings. His two losses were a tight, two-set loss to eventual champion Novak Djokovic in the 2023 edition semifinal and a third-set tie-break loss in the semifinal to Jannik Sinner last year, who went on to win the title. His record against Shelton also improved to four wins in four matches.

On the other hand, Alcaraz booked his semifinal spot in a nervy, error-filled outing against Andrey Rublev. The number two in the world has seen his share of highs and lows in the tournament. But Alcaraz prevailed by 6-3, 4-6, 7-5 in a match that went to an exciting decider, despite the 15 unforced errors and three double faults in the final set.

This is Alcaraz's 12th ATP Masters 1000 semifinal appearance.

Zverev has a slight edge over Alcaraz in head-to-head with 6-5. He has won five of his seven meetings with Alcaraz on hard surfaces, including the clash at last November's ATP Finals.

- ANI