When play begins Monday at the Western & Southern Open in Cincinnati, Serena Williams, playing her second-to-last tournament of her career, faces 2021 US Open champion Emma Raducanu.

Williams, who is more than two decades older than her 19-year-old opponent, was the top-ranked player in the world when Raducanu was born in November of 2002. 

Raducanu, at a career-high No.10 among Hologic WTA Tour players, draws the unseeded Williams, 40, who has played only three matches in the past 13 months. It’s their first meeting and, quite possibly, their last.

Call it what you will -- the torch being passed, ships passing in the night -- it’s a wonderful contrast and should provide some good theater as the tennis world continues to celebrate Williams’ career.

Cincinnati: Scores | Order of play | draw

“To see her around in this U.S. swing is really inspiring,” Raducanu said in Toronto. “She keeps playing because she obviously loves the game. And I think that longevity of a career is something that a lot of the players, and me especially, we aspire to achieve as well.”

How will this must-see matchup play out? We provide the case for both players:

Advantage, Raducanu

This looks and feels like it will be a close one.

Williams won her first-round match at the National Bank Open last week in Toronto before losing to Belinda Bencic in the second round. Speaking of random draws, Raducanu had the misfortune to face defending Canadian Open champion Camila Giorgi in the first round and went quietly after an entertaining first set, 7-6 (0), 6-2.

Cincinnati draw: Raducanu faces Serena Williams in blockbuster opener

It’s been a disappointing season for the British teenager. Despite that career-high ranking, she’s 11-14 so far. Still, Raducanu produced some encouraging results a few weeks ago at the Citi Open in Washington, D.C., before falling in the quarterfinals to eventual champion Liudmila Samsonova.

“To have success at a young age, obviously you have to be really grateful because I’m doing what I love, but also I’ve reached success way earlier than I ever really would have thought I did," Raducanu said. “So I’m pretty proud of myself in that way.

“But it has been a tough year. I’ve definitely gone through and experienced a lot of challenges. To be fair, I’ve learned a lot from all of it.”

Both women will be highly motivated to win this marquee match, but I’m thinking there is one (incredibly obvious) factor in play here that will swing this one: age.

Williams is arguably the greatest women’s player ever, but at 40 she’s understandably a step or two slower. Raducanu is quick around the court and, like the past three women to defeat Serena (Aliaksandra Sasnovich, Harmony Tan and Bencic), there will be no sense of nostalgia, no respect for elders.

A year ago, Raducanu raced through US Open qualifying and into the quarterfinals, never facing a Top 40 player in seven victories. And then she drilled Bencic (No.12) and Maria Sakkari (No.18) on her way to the final against fellow teenager Leylah Fernandez. That experience, the ability to focus on a big target, to stay in the moment, will carry her through this one, too. -- Greg Garber

Advantage, Williams

Can Serena Williams, at the age of 40, playing in her penultimate tournament on the road to retirement, defeat the 19-year-old reigning US Open champion? It's Serena Williams. Of course she can.

I was in Toronto last week for the National Bank Open and observed Williams on the practice and around the grounds. I can confidently say the 23-time major champion is not just going through the motions as she readies to hang up her racquets after the US Open. She is focused and intent on winning matches. Never underestimate the pride of a champion.

Williams has been putting in the work, which was evident in her first-round win against Nuria Parrizas Diaz in Toronto. Compared to her three-set loss to Harmony Tan at Wimbledon, which was her first singles match in nearly a year, Williams showed big improvements in every facet of her game. Her movement and anticipation were quicker, her serve was firing more consistently and her patience was rock solid. All those hours on the practice court have shaken off more of the rust.

The key to victory will be to keep Raducanu at bay with her serve while mitigating the Brit's opportunities to expose her movement out wide. When it comes to experience, Williams has it in spades. In a career that has spanned nearly two-and-a-half decades, Williams knows multiple ways to win and has solved more puzzles than Raducanu has yet to face in her young career. She has seen every situation and every ball that can come across a tennis court hundreds of times.

Just as important as the quality of her game is the level of Williams' motivation, and there is zero doubt that it would be stratospherically high as she faces Raducanu. Aside and apart from just getting wins to build momentum and go deep at one of her final tournaments, Williams would love to get a marquee win. A win over Raducanu would be precisely that. -- Courtney Nguyen

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