Britain's Arthur Fery beat Australia's James Duckworth at the Cincinnati Open, in his first match since making a shock run to the Wimbledon semi-finals last month.

Elsewhere, Novak Djokovic revealed he has an ongoing health condition as the 24-time Grand Slam champion struggled with the hot and humid conditions during a shock defeat by Argentina's Thiago Tirante.

Fery, who had jumped to a career-high world ranking of 36 following his Wimbledon success, won 6-4 2-6 7-6 (7-4) in two hours and 34 minutes against Duckworth in Ohio as he warms up for the US Open later this month.

The 24-year-old was given a wildcard into his home Grand Slam, having been ranked 114th in the world before the start of the tournament and having never been beyond the second round of a Grand Slam, and defied all expectations to reach the semi-finals where he lost to Alexander Zverev.

Following Wimbledon, he took some time off and then went into a training block at the National Tennis Centre in Roehampton.

Seeded 32nd in Cincinnati in what is just his second Masters 1,000 event, he will play Australian fifth seed Alex de Minaur in the next round.

Fellow Brit Cameron Norrie is out, losing 3-6 6-3 6-3 to Germany's top seed Zverev.

Djokovic suffers in heat as Tirante inflicts shock defeat

Djokovic dropped on to his hands and knees and took a medical timeout during the second set before losing 2-6 6-4 6-4 to Tirante, who is ranked 50th in the world.

"It was not an enjoyable match for me, for sure," Djokovic said. "The way I felt. Not the first and I guess not the last time, but it is what it is."

Djokovic, 39, the world number five, was making his first appearance since losing to Jannik Sinner in the semi-finals at Wimbledon in July.

The Serbian had never failed to reach at least the last 32 of the tournament in Ohio since making his debut in it in 2005.

Despite claiming the first set, Djokovic toiled badly after winning an 18-minute third game in the second set and appeared to vomit twice.

A physio and a doctor provided on-court assistance and both players returned to the dressing rooms after the second set.

When play resumed Djokovic dropped serve in the ninth game of the third set and Tirante was able to see out the match.

Djokovic said he is dealing with an underlying health condition.

"It's just a condition that I have, health-wise, that has been bothering me for the past couple of years," Djokovic said. "[It causes] a lot of issues, especially when it is humid and it is hot."

Tirante called the victory the "best win of my career", adding: "I managed the nerves of playing a legend like Novak. It was all so much pressure."