Everton have completed the signing of midfielder Amadou Onana from Lille.
Onana, who joined Lille from Hamburg in 2021 and made 43 appearances for the Ligue 1 side last season, has signed a five-year contract with the Toffees.
Frank Lampard has been eager to reinforce his midfield ranks, and Onana represents something of a coup for a club that finished 16th in the Premier League last term.
The 20-year-old Belgium international, who only made 15 starts for Lille, looked set to join West Ham, but Everton reportedly matched the Hammers' offer, agreeing a fee of £25.3million (€30m) with add-ons potentially taking the deal to £33.7m (€40m).
After sealing his move, Onana told the club's website his desire to learn from Lampard was a key factor in enticing him to Goodison Park.
"It feels great to join Everton. I know it's a big, big club, one of the biggest in England. It's something I want to be part of for many years," he said.
"Everyone here showed they really wanted me and they have a plan for me, so I really appreciated the talks I had with the manager and director of football [Kevin Thelwell]. They told me how they wanted me to play and I enjoyed it.
"They both have a lot of ambition and that's the type of guy I am, so it matches.
"The manager was one of the big reasons. He played at the highest level, won many things and was a midfielder, too. It means a lot to have interest from him and I think he can teach me many things."
Onana, who was in attendance as Everton lost 1-0 to Chelsea on Saturday in their Premier League opener, is set to be one of two midfield signings, with Idrissa Gueye on the verge of rejoining from Paris Saint-Germain.
Gueye was sold to PSG in 2019, having signed for Everton from Aston Villa in 2016.
Lampard, who brought in James Tarkowski, Dwight McNeil and Ruben Vinagre in July, is also keen to bolster Everton's attacking options, with striker Dominic Calvert-Lewin set to miss at least six weeks with a knee injury sustained in training, while Richarlison was sold to Tottenham in June for a reported £50m, with add-ons taking that fee to £60m.
The Toffees have also signed Wolves defender Conor Coady on a season-long loan after losing both Ben Godfrey and Yerry Mina to injury against the Blues.