Federer's fan plays Djokovic at US Open

Shelton caused a fever among the American audience when he became the youngest home player since Michael Chang in 1992 to reach the US Open semi-finals. Like his peer Carlos Alcaraz, Shelton idolizes Roger Federer.

The 20-year-old tennis player only decided to pursue professional tennis last year, when he gave up returning to the University of Florida. At that time, Shelton signed a contract with Team8 - a Swiss company representing tennis players, with Federer as one of the leading members. Team8 also currently represents another American star, Coco Gauff. Like Shelton, Gauff reached the Grand Slam semi-finals in New York this year.

Shelton and Gauff both use On Running shoes made by Federer's company. World number one tennis player Iga Swiatek also puts her trust in the Swiss shoe brand that Federer has promoted since the last few years of his career.

Shelton's parents, uncle and sister all played tennis. His father is professional tennis player and coach Bryan. The young tennis player is having a breakthrough season, reaching the ATP top 50 last month and will enter the top 20 after the US Open, despite losing 20 of 32 matches played.

Shelton is 1m93 tall, plays left-handed and has the fastest serve at the US Open this year, with a serve of 240 km/h in the match against Tommy Paul in round four. The serving record at Flushing Meadow belongs to another American, Andy Roddick with 244 km/h in 2004. Thanks to working with coach Scott Perelman at the University of Florida, Shelton is leading with 76 direct serves in the competition. US Open this year.

"He should have followed rugby when he grew up with a room full of pictures of the sport's stars," Mr. Bryan said of his son. "But I stopped him from choosing rugby, because I didn't want him to get hit in the head."

Shelton admitted that he did not have much ambition early in his career. He said: "I play tennis to have fun. That's why I always smile with my team. Going on the court and showing my full potential is what I want and have somewhat done this year."

Shelton will fight Djokovic in the semifinals of the US Open on the evening of September 8.