‘Baffling’ US Open blunder exposed

THE US Open celebrated a dream semi-finals line-up of four Americans in the 2017 women's singles.

12 months later, US Open officials have now admitted they deliberately changed the speeds of courts around Flushing Meadows in an attempt to help American players.

US tennis legend Jim Courier revealed while commentating for Amazon TV in America that officials believed American players would be more successful at their home slam if they slowed down the pace of the courts.

The decision, combined with the poor ventilation caused by the roof on Arthur Ashe Stadium, has turned the 2018 event into a nightmare for players.

The hot and humid conditions combined with the lack of air circulation in the grand slam's main arena has made the 2018 slam one of the most gruelling seen in recent years.

It has now been revealed that a slower court surface has also contributed to more brutal matches, longer rallies and tougher conditions for players.

Courier said the changes to the court surface were made solely to benefit American players, despite US Open tournament director David Brewer admitting last week that the courts were slowed down because of feedback last year that the courts had become too quick.

Courier's revelation was met with puzzlement by American tennis commentators.

It clearly backfired.

John Isner was the only American male to reach the quarter-finals - and is a player who has traditionally played his best tennis on fast courts that benefit players with big serves.

Just three American women made the round of 16 in the women's singles - but a dream final between Madison Keys and Serena Williams remains on track after the pair both won through to the semi-finals.

The slower court and humidity created a brutal backdrop for Rafael Nadal's five-hour epic slug-fest victory over Dominic Thiem where neither big-hitter was able to blast their opponent off the baseline.

The conditions also got the better of tennis legend Roger Federer when he was knocked out by Aussie John Millman in the fourth round.

"When you feel like that, everything is off, so," Federer said of his failure to deal with the humidity and the slower surface.

"Some days it's just not the day where the body can cope with it.

"I do believe since the roof is on that there is no air circulation in the stadium. I think just that makes it a totally different US Open.

"Plus conditions maybe were playing slower this year on top of it. You have soaking wet pants, soaking wet everything. The balls are in there, too. You try to play. Everything gets slower as you try to hit winners.

"Again, look, I thought the match was tough. I wish I could have led two sets to love and then maybe the match would be different, you know, and I would find a way, because I did have my chances all the way till the end. It was just tough. I thought John played a great match in difficult conditions."

Roger Federer revealed he struggled to breathe during his shock 3-6, 7-5, 7-6 (9/7), 7-6 (7/3) defeat to world number 55 John Millman at the US Open on Tuesday (AEST).

The 37-year-old five-time champion laboured to his earliest loss at the tournament in five years.