The US Open has been a tournament of shocks and surprises in recent history.

Upsets seem to be a regular occurrence at Flushing Meadows. Just last year, world number two Carlos Alcaraz lost in the third round to unseeded Botic van de Zandschulp in straight sets.

Four years ago, Emma Raducanu became the first qualifier to win a Grand Slam, and 12 years ago Marin Cilic – who recently defeated Jack Draper at Wimbledon – won the tournament while being seeded 14th.

Marin Cilic of Croatia celebrates with the trophy after defeating Kei Nishikori of Japan to win the men's singles final match on Day fifteen of the 2014 US Open at the USTA Billie Jean King National Tennis Center on September 8, 2014 in the Flushing neighborhood of the Queens borough of New York City. Cilic defeated Nishikori by a score of 6-3, 6-3, 6-3.Photo by Al Bello/Getty Images

One specific player, who reached a career high of world number 21 during his career, produced a remarkable feat at the 2008 US Open.

While competing at the tournament, this player was ranked 130 on the ATP Tour.

Gilles Muller’s remarkable run at the 2008 US Open

Gilles Muller came into the 2008 US Open ranked 130 in the world. Therefore, he was not expected to register a deep run at the tournament.

However, Muller proceeded to defy expectations, reaching the quarter-final stage. By doing so, he became the first Luxembourgish player to reach a Grand Slam quarter-final.

Muller navigated his way through three qualifying rounds before defeating a wildcard in the first round of the main draw.

He then defeated former world number two Tommy Haas in five sets, before taking down 18th seed Nicolas Almagro in a brutal five-setter: a match that included three tiebreak sets.

Gilles Muller of Luxembourg serves against Nikolay Davydemko of Russia during Day 9 of the 2008 U.S. Open at the USTA Billie Jean King National Tennis Center on September 2, 2008 in the Flushing neighborhood of the Queens borough of New York City.Photo by Matthew Stockman/Getty Images

The Luxembourgish star continued to impress in the fourth round, defeating fifth seed Nicolas Davydenko in four sets.

However, Muller ran into a rampant Roger Federer in the quarter-finals. The qualifier put in a spirited performance against Federer, before eventually losing 6-7 4-6 6-7.

Muller reached another Grand Slam quarter-final almost nine years later, at Wimbledon in 2017.

The former world number 21 won two ATP Tour singles titles in his career, both in 2017. He won the ‘s-Hertogenbosch Open and Sydney Open.

Roger Federer won the 2008 US Open

After defeating Muller, Federer defeated Novak Djokovic, who had won the first of his 24 Grand Slam titles earlier in 2008 at the Australian Open.

In the final, Federer defeated Andy Murray in straight sets to lift his fifth consecutive US Open title.

To this day, Federer holds the record for the most US Open Men’s Singles titles won consecutively.

Remarkably, this would end up being the last US Open title of Federer’s career. He reached the final twice more in 2009 and 2015, losing to Juan Martin del Potro and Novak Djokovic respectively.