Tennis LIVE: Cincinnati Open ace questions rules after opponent raises alarm bells

The Cincinnati Open is well underway, with the world's best players still looking for a spot in the last 16. World No. 1 Jannik Sinner has already booked his place in round four, and former finalist Carlos Alcaraz will be hoping to join him when he takes on Hamad Medjedovic.

World No. 1 and defending champion Aryna Sabalenka survived a huge scare in her own third-round match, as Emma Raducanu pushed her to the brink before losing 7-6 4-6 7-6. It was an impressive performance from Raducanu, who was told off by the umpire for communicating a little too much with her new coach, Francisco Roig, during the first set.

But the conditions have been brutal so far in Cincinnati. Cameron Norrie and Daniil Medvedev struggled with the heat over the weekend and things took a turn on Monday when Arthur Rinderknech collapsed in the middle of his match against Felix Auger-Aliassime, and retired a few games later. Play was then interrupted by a power cut, and later by a fire alarm. Express Sport will bring you the very best news, gossip and reaction from the Cincinnati Open.

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