Jose Antonio Reyes, the ex-Arsenal and Spain forward, has died in a car crash at the age of 35, former club Sevilla have announced.
Reyes was part of Arsenal's 'invincibles' squad that won the 2004 Premier League title without suffering defeat.
He also played for Real Madrid, Atletico Madrid and Benfica during his career, as well as winning 21 caps for Spain.
Sevilla said in a statement on Twitter: "We couldn't be confirming worse news. Beloved Sevilla star Jose Antonio Reyes has died in a traffic collision. Rest in peace."
Reyes started his career at local club Sevilla and returned to the Andalusian side in 2012, helping them to win three successive Europa League titles.
He left the club in 2016 and played for Espanyol, Cordoba and Chinese side Xinjiang Tianshan Leopard before returning to Spain to join Extremadura earlier this year.
The second division club said in a statement on their Twitter account: "With a broken heart Extremadura UD announce the death of their player Jose Antonio Reyes in a traffic accident."
Among those who have paid tribute is former Arsenal hero Thierry Henry who described his former teammate and fellow "invincible" Reyes as a "wonderful player, superb team mate and exceptional human being".
Arsene Wenger, who signed Reyes for Arsenal, he told the club on Saturday: "I am devastated to hear the terrible news about Jose.
"To his family and friends, all support from everyone in the Arsenal family. He will remain forever in our hearts."
Cesc Fabregas wrote a heartfelt message on Twitter reminiscing about the time he spent with Reyes, who he described as his "first great friend in the world of professional football, my room-mate, who always wanted to sleep with the air conditioning on even when it was -10 degrees."
The Monaco and Spain midfielder, who joined Arsenal as a 16-year-old 2003, also said Reyes was a "humble guy who always had a smile on his face, a great footballer and a phenomenal person."
"I'll never forget when you and your family welcomed me into your home during my first Christmas in England when I was alone and 16 years old.
He added: "I'll never forget our games of football tennis in the gym before and after training. Our connection on the pitch was also special."
Other former Arsenal colleagues including Freddie Ljungberg, Ray Parlour, Robert Pires and Abou Diaby shared tributes on social media too, along with current Gunners boss Unai Emery.
Ljungberg said he was "numbed by the news" about his former teammate, while Parlour described the former Spain international as a "great talent".
Emery tweeted his condolences in Spanish that translated as: "Deeply sad and speechless after learning of this tragic news. I'll never forget your magic and your smile Jose, never.
"It was an honour to be by your side...a strong hug and all the spirit of the world to family, friends and clubs he represented. RIP friend."
Arsenal's north London rivals Tottenham, meanwhile, paid their respects, tweeting: "All of our thoughts are with Jose's friends and family, and everyone at Arsenal at this very difficult time."
A minute's silence will be observed at Saturday's Champions League final as a mark of respect to Reyes.