Barcelona. Juventus. Porto... Bournemouth's transfer business this summer has seen them do deals with some of Europe's biggest clubs. It must feel somewhat surreal for their supporters who can clearly remember the days in League Two just 15 seasons ago.

But it is the arrival of the world's most expensive goalkeeper which really intrigues. The curious career of Kepa Arrizabalaga has taken another twist.

He was supposed to be "a big part of any success Chelsea have in the coming years," according to Marina Granovskaia when the London side splashed PS71.6m on him in the summer of 2018, smashing the record fee for a keeper which had been set by Liverpool with Alisson just weeks earlier.

The seven-year contract handed to Kepa was a rarity back in those days but underlined the belief Chelsea had in him. The 23-year-old seemed like a sure thing.

Datawrapper This content is provided by Datawrapper, which may be using cookies and other technologies. To show you this content, we need your permission to use cookies. You can use the buttons below to amend your preferences to enable Datawrapper cookies or to allow those cookies just once. You can change your settings at any time via the Privacy Options. Unfortunately we have been unable to verify if you have consented to Datawrapper cookies. To view this content you can use the button below to allow Datawrapper cookies for this session only. Enable Cookies Allow Cookies Once He certainly didn't lack belief in his own level at that time, infamously refusing to be substituted by Maurizio Sarri the following February during extra-time of Chelsea's penalty shootout loss to Man City in the Carabao Cup final at Wembley.

An apology and fine followed, with Kepa briefly dropped for Chelsea's next league game, but his status as No 1 was swiftly reaffirmed by Sarri and a couple of penalty saves in the Europa League semi-final helped the Blues towards a triumph in that competition at the end of his first campaign in west London.

But then Kepa's form turned. With Sarri gone and Frank Lampard brought in, Kepa's second season at Stamford Bridge was a poor one statistically: he let in 11 goals more than he would be expected to, according to the data. It was an alarming figure.

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"He makes far too many mistakes," said Sky Sports' Gary Neville at the start of the next season, when two errors in two games from Kepa saw him replaced by the Petr Cech-recommended Edouard Mendy.

Saturday 14th September 7:45pm Kick off 8:00pm Two seasons largely on the sidelines followed, with Kepa left to watch on as Mendy helped Chelsea to Champions League glory under Thomas Tuchel.

There was a morale-boosting cameo in the subsequent Super Cup win over Villarreal, when Kepa came on as a late sub for Mendy to save two penalties in the shootout - although his deployment as a shootout specialist backfired in the Carabao Cup final later that season when he failed to stop a single Liverpool penalty and then missed his own in the 11-10 defeat.

Image: Kepa Arrizabalaga refused to be substituted during the Carabao Cup final in 2019 A revival came under Graham Potter, with Kepa capitalising on a dip from Mendy and making the save of the 2022/23 season against Aston Villa, but Chelsea's hierarchy - now financed by Clearlake Capital and Todd Boehly - weren't convinced and signed Robert Sanchez as their next No 1, loaning Kepa to Real Madrid.

After the positive steps of the previous season, Kepa stumbled again. Real Madrid signed Kepa to cover for the injured Thibaut Courtois - who he had been bought in to replace at Chelsea initially - but he underwhelmed and lost his starting spot to Andriy Lunin, who he was sat alongside when Courtois made his comeback in time for the Champions League final triumph in June.

Another frustrating season finished with Kepa unsurprisingly left out of Spain's squad for their Euro 2024 win - he has just 13 caps.

With no clear route back at Chelsea for the foreseeable future, Kepa found himself badly in need of a reboot this summer.

Enter Bournemouth with the offer of a season-long loan to the south coast. A renegotiated contract with Chelsea saw Kepa accept a reduction in his hefty salary for a short extension and the opportunity to return to the Premier League. The Vitality Stadium may have been an unlikely destination but Bournemouth is a club with a familiar manager for Kepa.

The goalkeeper came through the ranks at Athletic Bilbao while Andoni Iraola was captaining the Basque side. Their career paths didn't see them play in the same team but they did train together and their connection was a key element to one of the window's most eye-raising deals being done.

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Highlights from Everton's match against Bournemouth in the Premier League. There were flashes of Kepa at his best during his dramatic debut win at Everton, saving sharply to keep out Iliman Ndiaye and Seamus Coleman from close range. That will have been encouragement for those Bournemouth fans watching on and wondering what they will get from their new No 1. They aren't the only observers asking that question.

Kepa will be back on the sidelines, unable to face his former club, when Chelsea come to the Vitality on Saturday night. But where his story goes next will be a fascinating storyline to follow this season.

Watch Bournemouth vs Chelsea live on Sky Sports Premier League on Saturday; kick-off 8pm

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