Southampton have agreed to sign Aaron Ramsdale from Arsenal in a permanent deal worth about £25m, including add-ons. Ramsdale will undergo a medical in the next 24 hours.

Saints will pay an initial £18m for the England goalkeeper, plus a further £1m if they avoid relegation from the Premier League. The rest of the financial package covers incentives.

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Southampton have been trying to bolster their goalkeeping options, with a move for Feyenoord’s Justin Bijlow collapsing at the medical stage. Arsenal had wanted about £30m for the goalkeeper, who is backup to David Raya, with Wolves walking away from a deal but a compromise has been reached with Saints.

Ramsdale, who spent three years at Bournemouth after joining from Sheffield United in 2017, is poised to return to the south coast on a long‑term contract. ­Bournemouth were also ­interested in the 26‑year‑old but instead moved to sign the out‑of‑favour Kepa Arrizabalaga on a season-long loan from Chelsea.

Stoke-born Ramsdale was at Wembley in fancy dress for Southampton’s Championship playoff final win over Leeds in May, dressed as Hagrid from the Harry Potter films, to support close friend and then Saints winger David Brooks, who has returned to parent club Bournemouth.

“Any time one of our friends get to Wembley we do fancy dress, it’s something we’ve done and we’ve won three times from it so we’re not gonna break from tradition now,” Ramsdale said, explaining his appearance.

Ramsdale’s expected departure could trigger Arsenal’s move for the Espanyol goalkeeper Joan ­García. Eddie Nketiah is expected to be another departure before the transfer deadline on Friday, with Crystal Palace keen to tie up a £30m deal.

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Bijlow – a Netherlands international with eight senior caps – had looked set to join Southampton from Feyenoord but revealed on Tuesday that his move to St Mary’s had been cancelled due to the results of his medical.

“Dear Feyenoorders, I was on my way to the Premier League,” he wrote on Instagram. “After a very special day last Sunday, for which I am very grateful, I was preparing for departure from Feyenoord.

“I didn’t find that easy and it wasn’t my first choice, but it had to be for the sake of my career.

“The medical examination has shown that Southampton has a different vision than Feyenoord on how to treat an old injury. I’m fully fit and this doesn’t bother me, but I respect the vision of Southampton medical staff. This is why I return to Rotterdam, to my club Feyenoord.

“My bond with the city and the club is iron strong. I keep fighting for a place in the goal of Feyenoord and the Dutch national team.”

Meanwhile, Crystal Palace look poised to sign Maxence Lacroix after agreeing a deal worth up to €21m (£17.7m)with Wolfsburg for the French defender. Palace’s initial offer worth up to £14m for Lacroix – who played under Oliver Glasner during his spell in charge of Wolfsburg – was rejected but Palace returned with a new bid in which they will pay €18m up front with €3m in potential add-ons.

The 24-year-old had entered the final year of his contract and is believed to have been keen to reunite with Glasner.

It is understood that Palace have yet to receive a new bid from Newcastle for captain Marc Guéhi having rejected several previous offers. The England defender played the entirety of Tuesday night’s Carabao Cup win against Norwich.

Palace are awaiting the results of a scan on Chadi Riad’s injured knee, with the Morocco international a major doubt for Sunday’s trip to Stamford Bridge.