Emma Raducanu felt like she was playing "two v one" as the Briton criticised umpire Ana Carvalho following her Nottingham Open first-round victory over Ena Shibahara.

The former US Open champion, who opted to miss the French Open to focus on preparing for the grass-court season, overcame the Japanese 6-1 6-4 in her first match since losing to Maria Lourdes Carla at the Madrid Open in April.

It was also Raducanu's first win on surface since the 2022 Wimbledon Championships, having missed last year's grass-court season after undergoing wrist and ankle surgery that, at one point, left her confined to a mobility scooter.

Although, the 21-year-old was left unhappy with several questionable decisions by umpire Carvalho, suggesting some of the calls were deliberately made in order to extend the contest.

It comes just 24 hours after fellow Briton Harriet Dart slammed "pretty appalling" officiating during her defeat to Katie Boulter in Nottingham, where electronic line-calling technology is not in use.

Nevertheless, Raducanu was pleased to eventually prevail and book her place in the second round.

"I feel like I was playing two v one on court, it was insane," said Raducanu. "I would have used probably at least four challenges!

"I think a lot of the time they go both ways. Today, I felt they were all against me, but it just makes me feel better that I managed to beat her and the umpire as well.

"It is difficult when there is no challenge, but it is something everyone has to deal with. You can be fortunate in some ways. Maybe it was just trying to make the match more competitive.

"It's something I had to deal with and overcome. I am very pleased with the attitude I came out with from the get-go and also having to deal with the adversity.

"I haven't played in a match for a while. Playing someone who comes through qualifying and is used to the conditions, I am very pleased to have won that match."

The world number 209 was also thrilled to get a win under her belt on home soil, and set up a last-16 clash with Ukrainian Daria Snigur, who defeated second seed Marta Kostyuk.

"An element of me forgot what it was like to play at home and have that support behind me, and it is amazing," she added. "It's a great feeling.

"I am very lucky to have great support wherever I play, but it's not quite like coming and playing in the UK. It's something that me and all the Brits cherish and look forward to every year."