Emma Raducanu pays tribute to Serena Williams after sealing win in Cincinnati

Emma Raducanu defeated Serena Williams 6-4 6-0 in their first and likely last encounter on the court.

Williams, 40, struggled to find consistency in just her fourth match of the season, giving up 12 unforced errors while making just 11 winners in the first round of the Western and Southern Open in Cincinnati.

Meanwhile, the 10th-seeded British player settled in to her rhythm early, breaking the 23-time major champion twice in the opening set before racing away in the second to claim her 12th win of the season.

The 19-year-old paid tribute to Williams, who announced her impending retirement from tennis earlier this month, in her on-court interview after the match.

"I think we all need to just honour Serena and her amazing career," she said.

"I'm so grateful for the experience of being able to play her and for our careers to cross over.

"Everything that she's achieved is so inspirational and it was a true honour to share the court with her."

Raducanu's victory sets up a second-round match with another WTA Tour veteran in Victoria Azarenka, who overcame Kaia Kanepi in the opening round.