Serena Williams bowed out of the WTA/ATP Cincinnati Masters at the first hurdle on Tuesday, losing in straight sets to US Open champion Emma Raducanu as the end of her glittering career looms ever closer.
Williams, who last week indicated that she is planning to retire after this month's US Open, was no match for British teenager Raducanu, who romped to a 6-4, 6-0 win.
The 40-year-old Williams left the court swiftly after the defeat without speaking to television reporters and did not hold a press conference.
Raducanu broke Williams at the start of both sets to claim victory in what was her first and likely last meeting with the 23-time Grand Slam singles champion.
"I was nervous from the first point to the last," Raducanu said. "Serena is dangerous and can come back from any situation.
"I had to stay focused. I'm so pleased I managed to keep my composure."
Williams, winner of Cincinnati titles in 2014 and 2015, was competing in only her fourth match of 2022 after starting her season at Wimbledon due to injury.
Raducanu announced her intentions from the start with a break to love of Williams and never let up.
The young Briton improved to 14 wins, 17 defeats since winning the Open last September from a qualifying start.
Raducanu meanwhile said she was honoured to be part of the spectacle on Tuesday in what was one of Williams' final games as a professional.
"We all need to honour Serena and her amazing career," she said. "I'm so grateful for the experience of playing her and for the fact that our careers have crossed.
"All she has achieved is inspirational. It's a true honour to share the court with her."
Raducanu never let Williams into the match.
The young Londoner seeded 10th took a 4-1 lead in the opening set and completely swept the second, advancing on her first match point, an unreturnable serve.
Raducanu committed a single unforced error in the opening set compared to a dozen for Williams.
Williams' elder sister Venus took a 7-5, 6-1 loss earlier in the day, losing to 2016 champion Karolina Pliskova.
In the men's draw of the joint event, Nick Kyrgios began the last major US Open tune-up with a 7-5, 6-4 win over Alejandro Davidovich Fokina.
The Australian marched through with 29 winners - including 10 aces - and three breaks of the Spaniard's serve to reach the second round.
The 28th-ranked Kyrgios has won all 11 of his first-round matches this season and won his 22nd match since returning to the ATP in June after skipping the clay season.
He now faces good friend Taylor Fritz after the American crushed Sebastian Baez 6-1, 6-1.
"Physically, I didn't feel the best, but you have to keep pushing, keep trying," Kyrgios said.
"Alejandro's a hell of a player, he's got a lot of shots at his disposal. I had to serve well and dictate," the Montreal quarter-finalist added. "It was tricky conditions out there, the courts are a lot more lively than Montreal, it was harder to control the ball."
It marked a happy return to Cincinnati for Kyrgios, who was fined a record $113 000 during a spectacular meltdown at the tournament in 2019
"I've played some amazing tennis here and had some crazy outbursts," he said. "It's a flip of the coin as to which Kyrgios shows up here."
Elsewhere, Spanish third seed Carlos Alcaraz advanced in his tournament debut, defeating American Mackenzie McDonald 6-3, 6-2.
Italian 10th seed Jannik Sinner celebrated his 21st birthday by beating Thanasi Kokkinakis 6-7 (9/11), 6-4, 7-6 (8/6).
Results from ATP/WTA Cincinnati Open on Tuesday (x denotes seed):
Tommy Paul (USA) bt Jenson Brooksby (USA) 6-3, 6-2
Taylor Fritz (USA x11) bt Sebastian Baez (ARG) 6-1, 6-1
Nick Kyrgios (AUS) bt Alejandro Davidovich Fokina (ESP) 7-5, 6-4
Fabio Fognini (ITA) bt Albert Ramos (ESP) 6-2, 6-3
Filip Krajinovic (SRB) bt Daniel Evans (GBR) 6-3, 6-4
Ben Shelton (USA) bt Lorenzo Sonego (ITA) 7-6 (7/5), 3-6, 7-5
Alex De Minaur (AUS) bt Henri Laaksonen (SUI) 6-2, 6-2
Jannik Sinner (ITA x10) bt Thanasi Kokkinakis (AUS) 6-7 (9/11), 6-4, 7-6 (8/6)
Borna Coric (CRO) bt Lorenzo Musetti (ITA) 7-6 (7/2), 6-3
Miomir Kecmanovic (SRB) bt Pablo Carreno Busta (ESP) 1-6, 7-5, 7-6 (7/4)
Carlos Alcaraz (ESP x3) bt Mackenzie McDonald (USA) 6-3, 6-2
Daniil Medvedev (RUS x1) bt Botic van de Zandschulp (NED) 6-4, 7-5
Jelena Ostapenko (LAT x16) bt Beatriz Haddad Maia (BRA) 6-4, 6-4
Marie Bouzkova (CZE) bt Cori Gauff (USA x11) 7-5, 1-0 abandon
Simona Halep (ROM x15) bt Anastasia Potapova (RUS) 6-4, 3-6, 6-3
Sorana Cirstea (ROM) bt Belinda Bencic (SUI x12) 6-2, 6-7 (3/7), 6-4
Marta Kostyuk (UKR) bt Camila Giorgi (ITA) 6-4, 5-7, 6-4
Emma Raducanu (GBR x10) bt Serena Williams (USA) 6-4, 6-0
Karolina Pliskova (CZE x14) bt Venus Williams (USA) 7-5, 6-1
Elise Mertens (BEL) bt Anhelina Kalinina (UKR) 6-1, 6-1
Anna Kalinskaya (RUS) bt Martina Trevisan (ITA) 7-6 (7/2), 7-5
Shelby Rogers (USA) bt Sofia Kenin (USA) 6-2, 6-1
Zhang Shuai (CHN) bt Naomi Osaka (JPN) 6-4, 7-5
Anett Kontaveit (EST x2) bt Tereza Martincova (CZE) 3-6, 7-5, 6-4