US Open: Andy Murray and Serena Williams win their first matches

Serena Williams with fans after her US Open first-round match

The US Open tennis tournament has gotten underway, and the first day of matches saw wins for USA's Serena Williams and Britain's Andy Murray.

Williams, who is set to retire after the tournament, played to a crowd of nearly 25,000 and said wins like this one make her decision to leave tennis harder.

Murray, one of seven British players at the US Open, showed determination to beat Argentine 24th seed Francisco Cerundolo.

Reigning champion Emma Raducanu starts her title defence on Tuesday, with seventh seed Cameron Norrie and Dan Evans also playing on day two.

Serena Williams is a six-time US Open champion, first winning back in 1999

Serena played Montenegro's Danka Kovinic and won 6-3 6-3.

She was cheered on by the huge crowd and after her win, the star spoke about her upcoming retirement: "It's extremely difficult still because I absolutely love being out there.

"The more tournaments I play, I feel like the more I can belong out there. That's a tough feeling to have, and to leave knowing the more you do it, the more you can shine.

"But it's time for me, you know, to evolve to the next thing. I think it's important because there's so many other things that I want to do."

Speaking about the crowd, Serena said: "I didn't expect any of this, I always have to do the best that I can. I have always felt so comfortable here. The crowd was crazy! It really helped pull me through. I was really pumped. I thought 'I got this'."

In the next round Serena will play Estonian Anett Kontaveit on Wednesday.

Kontaveit is ranked second in the world and is expected to be provide a big challenge in what could be William's final game.

Andy Murray extended his US Open first-round record to 15 wins and just one loss

Murray won his match against Argentina's Francisco Cerundolo with a score of 7-5 6-3 6-3.

On his win he said: "It felt like five sets to me, it was tricky conditions, very humid and hot.

"But I'm happy with the way I got through that one. He has had a brilliant year, I knew I had to play well and I did that in the important moments."

Murray, who earned the first of his three major titles in the US Open, will play 20-year-old American wildcard Emilio Nava next.

Jack Draper has climbed to 53 in the world rankings from 265 in January

Elsewhere in the competition, Britain's Jack Draper will join Andy Murray in the second round, after he beat Finland's Emil Ruusuvuori 6-4 6-3 6-3.

Fellow Briton Harriet Dart also advanced by overcoming 10th seed Daria Kasatkina.

The 26-year-old world number 88 claimed her first main-draw win in New York as well as her first victory against a top-10 player as she beat the world number nine 7-6 (10-8) 1-6 6-3.

But former British number one Kyle Edmund lost 6-3 7-5 6-2 against Norwegian fifth seed Casper Ruud as he made his Grand Slam singles comeback after a serious knee injury.

Emma Raducanu starts her title defence on Tuesday, with seventh seed Cameron Norrie and Dan Evans also playing on day two.

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