Casper Ruud's 'tough season' at Grand Slams and on the ATP Tour has continued at the US Open, where he has crashed out of his second-round match against Zhizhen Zhang. This comes at the same time as the fifth seed reached a major ATP Ranking milestone.

World No. 5 Ruud has had a difficult season. After crashing out of the Australian Open and Wimbledon in the second round, Ruud was hoping for a much deeper run at the last Slam of the season in New York, where he finished as runner-up last year.

The 24-year-old lost to Zhang in a five-set battle, which the Chinese player won 6-4, 5-7, 6-2, 0-6, 6-2. After the match, Ruud spoke of his disappointment.

"Yeah, it was tough obviously, disappointing to lose and the goal was to stay longer that's for sure, win more matches, but I have to give credit to Zhang, he came out firing from the forehand, from the backhand, served great and just made me a little uncomfortable at times," Ruud said.

Following his early defeat, Ruud will lose 1155 ATP ranking points, which sees him drop down from fifth to ninth in the Live Rankings.

Ironically, this comes as Ruud heads toward his 100th week in the top 10, after he broke into it for the first time on September 13th 2021. This is the third-longest active streak in the current ATP top 10.

The longest is held by 23-time Grand Slam champion Novak Djokovic, who has been there since July 16th 2018, totaling 243 weeks. Second is Stefanos Tsitsipas, who has spent 210 weeks in the top 10 after entering it on 4th March 2019.

Despite his recent troubles, Ruud managed to have a much more successful time at the French Open, reaching the final before losing to Djokovic.