Former Premier League footballer George Baldock has died at the age of 31.
The Greek defender was found on Wednesday in a swimming pool at his home in the southern Athens suburb of Glyfada, police sources told the Reuters news agency.
His cause of death remains unknown.
Baldock spent seven years at Sheffield United, having arrived from MK Dons in 2017.
He amassed over 200 appearances for the club before joining Greek side Panathinaikos earlier this year.
In a post on X, Sheffield United said the club is "shocked and extremely saddened" to learn of his death.
It said he was "extremely popular with supporters, staff and teammates" during his time at Bramall Lane.
Both Panathinaikos and the Greece national team blackened their profile pictures on social media on Wednesday evening.
The full-back, who was not named in the Greece squad to face England on Thursday, featured in Sunday's 0-0 draw with Olympiacos.
The Greek Super League said in a post: "The entire Super League football family expresses its deep sorrow for the untimely loss of Panathinaikos and our National Team footballer, George Baldock, and extends its deepest condolences to his family and loved ones."
England international and former Sheffield United player Harry Maguire posted "RIP" and a heartbreak emoji alongside an image of Baldock on Instagram.
Northampton Town, where Baldock had a loan spell in 2011, said it was "deeply saddened".
"George made five appearances in 2011 before playing for Oxford United and Sheffield United. Sending our sincerest condolences to George's family and friends," the club's statement read.
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Born in England, but with Greek ancestry in his family, Baldock was convinced by then-Greece head coach Gus Poyet to play for the national team and went on to earn 12 caps, last playing for his country earlier this year.
He also previously played for Oxford United and Tamworth.
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