On a day where young stars Carlos Alcaraz and Holger Rune practiced together in the hopes that they’d soon be back on the tour, another young gun found himself on the sidelines. 

Brazil’s Joao Fonseca pulled out of the Cincinnati Open due to an abdomen injury on his left side, the 19-year-old handing a walkover to Australia’s Christopher O’Connell. 

“Today during practice I felt a slight discomfort on the left side of my abdomen,” Fonseca wrote on Instagram. “After undergoing tests, my team and I decided to withdraw from the Cincinnati Open to recover as quickly as possible.” 

The news is a difficult blow to a young talent who hasn’t been able to get his body to cooperate in 2026. Fonseca started the season late due to a back injury, going 1-3 in the first two months of the season, but did find his game – and fitness – on the clay, where he defeated Novak Djokovic in a dramatic five-setter in the third round at Roland Garros. 

Fonseca went on to reach his maiden Grand Slam quarterfinal by defeating Casper Ruud, and eventually fell to Jakub Mensik in Paris. 

The injury is thought to be minor, but the timing couldn’t be worse, with the US Open’s main draw starting in less than two weeks. 

Fonseca is 19-13 on the season with three quarterfinals – at Roland Garros, Monte-Carlo and Munich – to his name.