Emma Raducanu was knocked out in opening round of the US Open by Sofia Kenin in a battle of former Grand Slam champions on Tuesday night in New York.

Raducanu has struggled to recapture the magic of her fairy-tale run at Flushing Meadows three years ago when she became the first qualifier to win a Grand Slam.

And American Kenin sent Raducanu packing with a 6-1 3-6 6-4 victory in front of a sparse crowd on Grandstand.

An emotional Raducanu wiped away tears when asked how she was feeling during her press conference.

“I feel down, I feel sad. Obviously, this is a tournament I really want to do well in so… after the first set I was outplayed completely and I think I did well to equal it,” she said.

“The third set was pretty high-level tennis and I think certain parts of my game in dealing with her speed of shot, dealing with her pace, certain parts I actually executed better than in previous matches.

“I came across a very in-form opponent, and she played really well.”

Kenin ripped through the opening set by winning six straight games before Raducanu, who reached the fourth round at Wimbledon this year, upped her level in the second set.

The Briton had missed three break points of her own in the first set, but made a move at the start of the second by taking Kenin’s serve.

Kenin recovered the break straight back but a crucial point at 2-2 and 15-15, where Raducanu hit a backhand winner down the line, changed the momentum of the second set.

It helped her break, with 2020 Australian Open champion Kenin losing her cool by hitting the ball into the backboard. Two brilliant winners saw Raducanu take a second break and the second set in style.

However, Raducanu ran out of steam, dropping serve with a double fault in the fifth game of the decider as she was broken and there was no way back from there as Kenin clinically saw it out.

Having played just one tournament since Wimbledon and skipping the Olympics to focus on her preparation for the US Open, Raducanu will be desperately disappointed to fall at the first hurdle and questions remain over the direction of her career.

In her defence, it was a tough draw for Raducanu against the former world No 4, who showed some of her best form.

Raducanu plans to go back to the drawing board before playing at the Korea Open in Seoul on September 16 – live on Sky Sports Tennis.

“Until then, I’m just going to go back to the drawing board and train and analyse where I went wrong and try and improve for the rest of the season,” Raducanu said. “Obviously the Slams are over for this year, but it’s not actually that long until Australia comes around again (in January).”

Carlos Alcaraz was given a scare by Australian qualifier Li Tu before going on to seal a 6-2 4-6 6-3 6-1 victory.

The 21-year-old, who won the US Open in 2022, showed no signs that his movement was limited by a right ankle injury he suffered during a practice session on Saturday.

He extended his Grand Slam match-winning streak to 15 against the world No 186 qualifier.

“Obviously, it surprised me a little bit. The first set, it was obvious that he started the match nervous. But after the first set, I think he started to enjoy it and play great tennis,” Alcaraz told on-court interviewer Nick Kyrgios.

“I was playing great, probably a few mistakes that I had. He is a great player. I’m going to follow him – his results – from now because I’m pretty sure if he is playing at this level, I’m going to see him around very, very soon.”

Up next for Alcaraz is 2021 quarter-finalist Botic van de Zandschulp, who beat Denis Shapovalov 6-4 7-5 6-4.

Frosty reception for Sinner

World No 1 Jannik Sinner admits he has endured a frosty reception from fellow players at the US Open following his failed anti-doping tests controversy.

The Italian was playing his first match since he escaped a ban despite two failed tests earlier this year.

Sinner, who was cleared of fault or negligence by an independent tribunal, has defended himself stoutly amid criticism he was shown favouritism with the speed in which his case was resolved.

It initially looked like the drama had taken its toll as American Mackenzie McDonald won the first set and then had a break of serve in the second, but Sinner assumed control and earned a 2-6 6-2 6-1 6-2 first-round victory.

Sinner said he had been pleased by the crowd’s reaction, but locker room reception had been a bit cooler.

“I’m curious to see how the reaction of the fans has been, but it has been very positive,” he said.

“I was very glad how the support was, also playing against an American, it’s a little bit different.

“So I’m happy [with] how I handled those situations, it was not easy. So I think a lot of positive things from today, and so let’s keep seeing what’s coming in the next round.

“There are some reaction from other players. I cannot really control what they think.

“You know, that’s how everything went and how it was. I cannot control the players’ reaction, and if I have something to say to someone, I go there privately, because I’m this kind of person.

“Overall, it has been not bad. So I’m happy about that.”

Former champion Daniil Medvedev booked his place in the second round with a 6-3 3-6 6-3 6-3 win over Serbian Dusan Lajovic.

Stefanos Tsitsipas became the highest seed to be knocked out after losing to Australian Thanasi Kokkinakis in four sets.

Felix Auger-Aliassiame, seeded 19th, also lost.

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