Former Sheffield United star George Baldock was found dead in a swimming pool at his home in Greece.
The 31-year-old defender was discovered after his wife in England was unable to contact him for several hours, local newspapers reported.
Other Premier League players including Harry Maguire paid tribute to the footballer – with the former Manchester United captain simply posting 'RIP', alongside a broken heart emoji.
Baldock joined Panathinaikos in the summer after spending seven celebrated seasons with the Blades, where he was nicknamed 'Furious George', in the Premier League and Championship.
Despite being born in Buckinghamshire, he played 12 times for Greece. He began his career with MK Dons and has played in all five of England's top divisions.
Former Sheffield United defender George Baldock has reportedly died aged 31 in Greece
The scene where former Sheffield United defender George Baldock was found dead in his swimming pool in Athens, Greece
George was living in this property in the Greek capital after moving to club giants Panathinaikos
Baldock says goodbye to fans ahead of the Premier League match between Sheffield United and Tottenham Hotspur at Bramall Lane
Police secure the area in front of the home of British Panathinaikos and Greek defender George Baldock, where he was found dead, in the suburb of Glyfada, Athens
The footballer moved to Greek club Panathinaikos in the summer and was found dead in their swimming pool on Wednesday.
Baldock was a mainstay of English football before leaving and also played 12 times for Greece
He was left out of Greece's latest squad, which will face England in the Nations League at Wembley on Thursday, after suffering an injury that ruled him out in September.
Baldock's wife reportedly tried to contact him for several hours without a response, before contacting the owner of his villa in Glyfada, a suburb south of Athens.
After searching the suburban property, they found Baldock in the communal pool and called emergency services.
He was reportedly in the water for several hours before being found, according to footage seen by the response unit.
A heartbroken Sheffield United paid tribute to their former player as they announced the news to their fans.
'Sheffield United Football Club is shocked and extremely saddened to learn of the passing of former player George Baldock,' they posted on X.
“The defender left the club in the summer after seven years at Bramall Lane and was hugely popular with fans, staff and team-mates who donned a red and white shirt alongside him.
'The sincere condolences of everyone associated with Sheffield United are extended to George's family and friends.'
A heartbroken Sheffield United paid tribute to their former player by announcing the news to their fans
Northampton Town, where he played five games on loan, wrote in X: 'We are deeply saddened to learn of the passing of former loanee George Baldock at the tragically young age of 31.'
And his boyhood club MK Dons said he was 'devastated' to hear the news, in an emotional post saying he 'will always be one of us'
English football's official account said it was “extremely saddened” after hearing the news
England defender Harry Maguire was one of the first to react, writing 'RIP' on Instagram
Police secure the area in front of the home of British Panathinaikos and Greek defender George Baldock, where he was found dead, in the suburb of Glyfada, Athens
Northampton Town, where he played five games on loan, wrote in X: 'We are deeply saddened to learn of the passing of former loanee George Baldock at the tragically young age of 31.
“Sending our deepest condolences to George's family and friends.”
Panathinaikos appear to have deleted their logo on social media in a subtle tribute.
And his boyhood club MK Dons said he was “devastated” to hear the news, in an emotional post saying he “will always be one of us”.
They said: 'We are deeply devastated and saddened to hear the shocking news from former Academy graduate and MK Dons player George Baldock.
'George began his career at Stadium MK, where he came through the youth ranks and made his senior debut for the club before rising to the top of the Premier League in later years.
“Everyone affiliated with MK Dons shares a great love for George, Sam and the Baldock family, and we would like to share our deepest condolences during these terrible times.
'You will always be one of ours, George.'
Baldock, 31, was starting a new life in Greece before he passed away
The defender earned the nickname 'Furious George' due to his aggressive style
Also responding to the news, the official English football account said it was “extremely sad”.
They continued: “We are extremely saddened by the passing of George Baldock.
“George was close to many of our players and represented Greece – our opponents on Thursday night. We are thinking of George's family, friends and teammates at club and country at this difficult time.
The English Football League added that he made a “lasting impact” with his spells at Sheffield United, Oxford United, Northampton Town and MK Dons.
The Greek Super League also shared its “deepest condolences” following the news.
They said: 'The entire Super League football family expresses its deepest regret at the untimely loss of Panathinaikos and national team footballer George Baldock and extends its deepest condolences to his family and loved ones.'
Baldock was a long-time pillar of English football, making 219 appearances for Sheffield United alone.
He was promoted to the Premier League twice with the Yorkshire side.
After his wife was unable to contact him, the villa owner searched the property and found him in the pool
Baldock played in the Premier League and Championship with Sheffield United for seven years
At Bramall Lane he earned the nickname 'Furious George' due to his combative and aggressive style on the field.
'Since arriving at this club I quickly realized that the tougher the opposition, the more you had to find a way to get an advantage over your opponent,' he once told the Sheffield Star.
'To be honest, I really like it. Plus, I love winning. I hate losing and I even hate drawing.
Even when we're playing pool in the recreation area during training, that competitive streak comes out.
'The only problem is, when it comes to potting balls instead of kicking them, I'm not very good at it.'
Baldock played just four games for Panathinaikos, including one in the Europa League – a new adventure for a player whose experiences were mainly limited to domestic football.
