Emma Raducanu dispatched her second Grand Slam champion in less than 24 hours on Wednesday at the ATP and WTA Cincinnati Masters by crushing Victoria Azarenka 6-0, 6-2.

The teenaged US Open champion claimed the first 10 games before her veteran opponent, a two-time Cincinnati winner with two Australian Open titles, finally captured a game.

But the young Briton, who ousted Serena Williams the night before with another love set, was having nothing of the sort.

Raducanu calmly achieved 5-1 and conquered her nerves two games later by saving two break points and serving it out on her second match point as Azarenka drove a return long after 63 minutes.

The heavy defeat continued bad form at the US Open tuneup for Azaranka, the 2013 and 2020 winner, who won only two games here a year ago in a third-round loss to eventual champion Ashleigh Barty.

"I played a great match for sure," 10th seed Raducanu said. "To play Vika like that I had to stay focused.

"In the second set I could feel the important moments. I'm pleased with how I dug in and served it out.

"It was an honor to play Vika. She has won so many championships. It was great for me to be out there."

On the men's side, Andy Murray needed a post-match on-court visit from the trainer after going down 3-6, 6-3, 6-4 on to Cameron Norrie in the second round.

Murray, a two-time Cincinnati champion, needed massage on his right thigh before being able to leave the court after battling for nearly two and three-quarter hours in the last major tuneup for the US Open, which begins August 29.

"At times I felt like I played really well and then at times didn't. My consistency maybe was not where I'd want it," Murray said.

"But there was some positive tennis in there at times. I definitely had enough opportunities to win that match."

After cramping at other events in recent weeks, the 35-year-old is concerned about his physical situation.

"It's a big concern for me. It's something I need to address and find a solution for," Murray said.

"No one knows exactly why cramps happen. There are many reasons, whether it's hydration, food, fatigue, lack of conditioning, stress.

"You need to try and understand what's going on there."

World number 11 Norrie broke open a slow-moving match stalemate with a service break in the penultimate game of the final set, sending a passing shot to the baseline behind a frustrated Murray, and advanced into the third round moments later, converting on his first match point.

"We had a couple of break chances in the second and third sets, I just played the bigger points a bit better," Norrie said. "It came down to one or two points."

Norrie produced 39 winners to 37 for three-time Grand Slam champion Murray, the pair now 1-1 in a sparse career series.

Murray converted on only two of his 11 break chances and fired nearly 40 unforced errors.

"I was not physical enough at the start of the match," Norrie said. "I was not executing the way I liked.

"All credit to Andy, it was not easy at the end but I managed to find a way. I was pleased to get through without playing my best."

Elsewhere in the second round, sixth seed Andrey Rublev advanced past Fabio Fognini 6-7 (7/9), 7-6 (7/3), 6-2 and Canadian seventh seed Felix Auger-Aiiassime beat Australian Alex de Minaur 6-3, 6-2.

In the women's draw, Wimbledon finalist Ons Jabeur of Tunisia, the fifth seed, defeated Cincinnati's own Caty McNally 6-3, 4-6, 7-6 (9/7). (AFP)