Raducanu, 19, has been drawn against the 23-time Grand Slam champion in the first round of the Western and Southern Open, which is regarded as the second biggest tournament on the North American swing after the US Open.
The blockbuster encounter will give Raducanu the chance to face Williams before the tennis legend intends to retire after the US Open in September.
But when does the historic match take place, and how can you watch it in the UK?
Here’s everything you need to know about the clash.
When does Emma Raducanu play Serena Williams?
Raducanu and Williams are scheduled to take to the court tomorrow (August 16).
The match was set to take place on Monday, but there was a last-minute pushback.
A spokesperson for the tournament said the change was ‘on account of a number of factors related to scheduling.’
The exact time has not yet been announced, although it is likely that organisers will give the match a prime-time slot in the evening session on centre court.
Given the time difference between Cincinnati and the UK, British fans hoping to watch the match will likely have to stay up late into the evening or the early hours of Wednesday morning.
Raducanu will be just the fourth British tennis player to face Williams, after Heather Watson, Laura Robson, and Jo Konta.
The winner of the match will play either Victoria Azarenka or Kaia Kanepi in the second round, with the match likely to be played on Thursday, August 18.
How to watch the Emma Raducanu play Serena Williams in the UK
The match will be shown live on Amazon Prime Video for viewers in the UK.
Amazon Prime and Prime Video members can watch the game via mobile, app, online, Fire TV, BT TV, TalkTalk TV, Virgin’s V6 TV Box, Apple TV, or Chromecast.
Fans without a membership can still watch the match by signing up for a free 30-day trial.
Amazon Prime membership is available for £7.99 per month or £79 for the year.
What has Emma Raducanu said about facing Serena Williams?
Raducanu has expressed her delight at getting the chance to face one of her tennis idols before Williams retires from the tour.
She said: ‘I think it’s gonna be an exciting match. I’m looking forward to it. It’s an amazing opportunity to play probably the best tennis player of all time. It’s probably going to be my last opportunity to ever play her.
‘I think that, for our careers to have crossed over, I think I’m really fortunate that I get to play her. Whatever happens, I think it’s gonna be a really good experience for me and something that I will remember for the rest of my life.
‘It’s a great gift to play the best on her way out from the sport. So I’m just looking forward to that.
‘Expectations, I don’t really know, I don’t really care. I just want to go out there and, one, enjoy the match that I’m going to play whenever I do play it.’
Raducanu went to Wimbledon as a youngster to watch Williams, and it is a cherished memory she will never forget.
She said: ‘I remember the highlight of my year was when I was young, at a tennis club, my first coach would take me and one other boy to Wimbledon on my day out.
‘We got on to Centre Court somehow and we watched her annihilate someone one and one. That was just really cool to see her live. That day out with my first coach, I was so excited for the day. I think that was a really special time in my life, a memory that I’ll always have.’
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