Everton have signed Republic of Ireland defender Jake O'Brien from Lyon for £17m.
The 23-year-old centre-back has signed a four-year deal and returns to the Premier League, having only joined the Ligue 1 club from Crystal Palace last year.
However, he went on to play 27 times in the French top flight, scoring four goals.
Since then, the 6ft 6ins defender has gone on to make his international debut, featuring twice for the Republic of Ireland in their June friendlies.
"I'm buzzing and so happy to have signed for Everton," O'Brien told evertontv. "I've been dreaming of this kind of move in the Premier League, with such a historic club. It's a very exciting move for me.
"When the transfer window opened there were other clubs in for me but there was only one club I wanted to go to – it was Everton.
"They've shown the faith in me so now it's my turn to show why on the pitch.
"You see how Sean Dyche develops young centre-halves and what he has done for Jarrad [Branthwaite]. The way he's going now, the season he's had in the Premier League, it's obviously something I look at and something I want to replicate.
"This season, I just want to play as many games as I can and help the club get higher up the table. It's an exciting time and it'd be good to end the season – the last season at Goodison Park – as high up the table as we can."
On his respect for Seamus Coleman, now his captain for club and country, O'Brien added: "Seamus has been on to me to sign for Everton! He's a top guy, a brilliant captain, and to play under him here as well as with Ireland will be a privilege.
"He's the best captain I've ever played under. He's massively respected – not just here but in the football world in general.
"I've met all of the lads in the squad and you can sense straight away that it's a tight-knit group. Obviously, having Seamus here will help me as well."
After securing his fifth signing of the summer, Everton manager Sean Dyche said: "Jake further strengthens our talented core of centre-backs and adds competition to our squad which can help us continue to progress.
"He is still young but has earned valuable experience both abroad and at international level, and has many impressive attributes to become a top-quality player for Everton in the Premier League."
O'Brien turns Goodison into 'Land of the Giants'
Sky Sports' Ben Grounds:
Just 12 months after becoming the first Irishman since Tony Cascarino in 2000 to play in Ligue 1, O'Brien is returning to England for an eight-figure sum.
Having joined Lyon for €1m (£850,000) from Crystal Palace, the French club – who must generate €100m in player sales this summer to meet the demands of the country's football's financial watchdog – are making a quick and sizeable profit.
O'Brien did need long to establish himself as a mainstay after Pierre Sage's appointment. Back in December, he was voted Lyon's player of the month. By May, he was scoring in the 2024 Coupe de France final against PSG.
With just two Republic of Ireland caps to his name, his progress has been steady since a successful loan spell at RWD Molenbeek, contributing to the club's championship title and promotion to the Jupiler Pro League.
However, he failed to make a professional appearance across three years at Crystal Palace.
O'Brien, at 23, has already been on the scene for some time, spending the second half of the 2021/22 season on loan at Swindon Town in League Two. Like Coleman, who joined Everton aged 20, he could be classed as a late bloomer. That is not where the similarities with the club's record Premier League appearance-maker end.
Coleman, a Killybegs native, was a talented Gaelic footballer before committing to association football, while O'Brien won the national championship of hurling aged 14 in addition to being a talented boxer – physical attributes he has transferred across the two sports.
Despite his height, Everton's latest recruit recorded a speed of 35 km/h during a recovery sprint against Rennes last season, showcasing his pace across the ground honed in his formative years.
Sean Dyche will have warmed to his unusual journey that has brought multiple experiences already at such a young age, while he is also recruiting a goal threat; only Alexandre Lacazette (19 goals) scored more than O'Brien's five in 32 matches for Lyon last term.
The Everton boss sold Amadou Onana to Aston Villa earlier this month, and while the Belgian occupied a different position, one of his biggest qualities was at set pieces in both boxes – an area in which O'Brien excels.
Everton don't see the centre-back as a replacement for Manchester United target Jarrad Branthwaite but rather the latest youthful recruit under the guidance of director of football Kevin Thelwell. All four summer signings are aged 24 or under.
James Tarkowski alongside Branthwaite will be expected to remain the first-choice pairing – but Everton continue to look to the future. Tarkowski turns 32 in November while they could not afford to go into another campaign with Michael Keane and Mason Holgate as the next in line.
O'Brien will back himself to hit the ground running and his ceiling is very high. It has to be. Premier League opponents will be arriving in the Land of the Giants on their final visit to Goodison Park.
'Brave as a lion' – O'Brien's unusual journey
Sky Sports' Adam Bate spoke to O'Brien's former coaches to find out more:
It was in the first half of Molenbeek's game against Beveren in April of last year that it happened. Molenbeek's best defender contested a duel with the opposition striker and emerged from it with a broken nose. The blood was streaming down his face.
"There was a lot of it," Jonathan Alves tells Sky Sports. Alves was Molenbeek's assistant coach and feared the worst, for player and team. "This was first against second and we were sure he was going to stop. It was impossible. But he just cleaned himself off."
Alves still remembers the moment that this Irishman turned to the Belgian crowd and urged them to roar their support. "Within minutes, he was delivering a top performance. If you want to know who Jake O'Brien is, just watch that game and see what he did."
It feels a little uncomfortable to praise such bravery when there would have been no shame in going off. But for those involved, this was a defining moment in Molenbeek's title win. "A big game, lots of pressure? Let's go. That is my best memory of Jake."
What will Everton be getting with O'Brien?
French football expert Jonathan Johnson on The Transfer Show:
"Jake O'Brien's rebirth with Lyon has been fascinating over the last year or so. He came in with no real expectation around him into a squad that was really low in confidence and really struggled in the first half of last season.
"But he ended up emerging from the end of the campaign as one of the team's most consistent performers, chipped in with some really crucial goals as well and reminded people of the fact that he's a very talented and capable defender, imposing and a threat from set-pieces as well.
"When you look at the reasonably good value for money this deal represents and the fact it is a significant profit for Lyon based on what they paid to bring him in initially, I think this is one that suits all parties."
When does the summer transfer window open and close?
The 2024 summer transfer window officially closes on August 30 at 11pm UK time in the Premier League and 11.30pm in Scotland.
The Premier League has brought forward Deadline Day to link up with the other major leagues in Europe. The closing dates were set following discussions with the leagues in England, Germany, Italy, Spain and France.