Mats Wilander has raised a 'warning flag' for Coco Gauff ahead of her semi-final clash with Karolina Muchova at the US Open, saying she will need to think hard about how to outwit her opponent.

Gauff has had a dream run at the US Open so far, where she is the home favorite to take the title in women's singles. She has flown past the likes of Mirra Andreeva, Elise Mertens, and Caroline Wozniacki before ousting twentieth seed Jelena Ostapenko in straight sets.

Meanwhile, World No. 10 Muchova has defeated Magdalena Frech, Taylor Townsend, Xinyu Wang and Sorana Cirstea on her way to the semi-final clash with the sixth seed.

Eurosport expert and former World No. 1 Wilander has warned Gauff to keep her wits about her in the clash, despite having defeated Muchova in the final of the Cincinnati Open a couple of weeks ago.

"I have to throw a warning flag," he said.

"Even though Coco beat her in Cincinnati, Muchova has the game that can assess the situation, play risky tennis, realise it doesn’t work, then do something different."

The Swedish former player also added that Gauff would need to have her 'thinking cap' on throughout the match.

"Coco really needs to put on her thinking cap when she plays Muchova.

"This is an opportunity as a 19-year-old. She is young but this is an opportunity she needs to take, I think," he continued.

The American and the Czech player are both aiming for their first Grand Slam title in New York. They have also both reached one major final where they finished as runner-up, with 19-year-old Gauff making the final of the French Open in 2022 and Muchova finishing second at the same tournament this year.