Serena Williams has kicked off her latest quest for an elusive 24th grand slam singles title with a straight-sets win over compatriot Kristie Ahn in the first round of the US Open.

Williams needed just under one-and-a-half hours to come through 7-5 6-3 despite falling a break down to her world No.96 opponent in both sets.

Four straight games turned the second set on its head and enabled Williams to belatedly find the momentum she required to claim victory.

Showing early signs of nerves, the former world No.1 then found another gear to fire off 13 aces and 28 winners.

A final serve forced Ahn into an error, handing Williams her 102nd US Open match victory, as she scored her first straight-sets win since the sport was put on a coronavirus hiatus.

“I was really happy with how I just fought for every point,” Williams said in an on-court interview after the match.

She had to regain her focus, she added, and “just be Serena and close it out.”

Spain’s Garbine Muguruza, looking determined to overcome her US Open jinx, beat Japan’s Nao Hibino to collect a snappy 6-4 6-4 first round win.

Flushing Meadows has not been a happy hunting ground for the former French Open and Wimbledon champion, who this year nearly added to her collection of grand slam trophies by reaching the final in Australia.

In stark contrast to her success at the other slams, Muguruza has struggled to make an impact on the New York hardcourts.

She has made it past the second round just once in seven previous visits to Flushing Meadows.

“I was anxious a little bit because I did not play in the last six months and did not have a chance to play before the US Open to get ready for here,” said Muguruza.

“I am happy with my performance I was expecting a tough match and it was.”

Australian Open champion Sofia Kenin produced a dominant display to dispatch Belgian Yanina Wickmayer 6-2 6-2.

American Kenin, who has lifted two titles in 2020 including her maiden grand slam triumph in Melbourne, broke her opponent in the first game to set the tone for the match before claiming the opening set in just 37 minutes.

The 21-year-old started the second set just like the first to take an early lead and went on to serve out the match in clinical fashion.

“I knew I could dominate her,” Kenin said. “Today I felt like I couldn’t miss a ball. I played really good tennis and I’m proud of myself.”

No.7 seed Madison Keys needed just 55 minutes to beat Timea Babos 6-1 6-1 as the 2017 finalist looks to claim her elusive first grand slam title.

The hard-hitting American won 92 per cent of her first serve points and never faced a break point while playing smothering defence against the overmatched Hungarian.

In an all-British affair, Johanna Konta shrugged off some early resistance before overpowering Heather Watson 7-6 (9-7) 6-1.