Keys, who won the Australian Open in 2025, said: “Eastbourne is an event that means a lot to me, it’s very special to come back as a former champion.
“I’ve had some great memories here and love playing in front of the fans.”
Brighton’s Sonay Kartal is also set to play.
The 24-year-old said: “Eastbourne has always been a special tournament for me. I grew up just a few miles down the road and used to come with my school to watch the world’s best in action.
“Those early memories were super inspiring and are probably part of the reason I’m where I am today.”
World number-89 Oksana Selekhmeteva was taking part in the tournament for the first time and said the vibe was “a little bit different compared to London”.
“It’s [my] first time here so I’m enjoying [it], but of course the big goal is Wimbledon.”
Rebecca James, tournament director at the Lawn Tennis Association (LTA), added: “Devonshire Park is a very special setting.
“It is the last week before Wimbledon, the last opportunity for players to hone their grass court match practice.”
She also said it was a “charming setting, being by the sea”.
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