Gemmell starred in the 1967 European Cup final.
Lisbon Lions legend Tommy Gemmell has passed away at the age of 73, Celtic have confirmed.
The former Scotland international died following a long illness.
Gemmell will be remembered for scoring Celtic's equaliser in May 1967, as Jock Stein’s side defeated Inter Milan, to become the first British team to lift the European Cup.
In addition to the European Cup success, Tommy won six league titles, three Scottish Cups and four League Cups throughout the 10 years he spent with Celtic.
He scored in the 1970 European Cup final, which Celtic lost to Feyenoord, and was also capped 18 times for Scotland.
A statement on the Celtic FC website reads:
"Tommy Gemmell is a true Celtic legend, part of the greatest side in the club’s history and a man who played a pivotal role in our greatest ever triumph when, in Lisbon’s Estadio Nacional, 11 men all born within a 30-mile radius of Celtic Park, beat Inter Milan to win the European Cup."
"The legend of the Lisbon Lions was created that night, and Tommy and his team-mates were assured their place in the pantheon of Celtic greats."
"The whole Celtic Family is mourning his passing, and everyone associated with the club sends their thoughts and prayers to his family, his fellow Lions and his many friends at this desperately sad time."
Tributes are being paid to Gemmell online:
Sad news hearing Tommy Gemmell has passed away.. Celtic great thoughts are with his family and close friends, RIP Tommy. 🍀🙏— John Hartson (@JohnHartson10) March 2, 2017
Tommy Gemmell— Celtic Collectibles (@CollectCelticFC) March 2, 2017
1 European Cup
2 European Cup Final Goals
6 Lge Titles
3 Scotttish Cups
4 Lge Cups#CelticLegend
Tommy Gemmell's goal against Benfica in Round 2 of the European Cup 1969/70.— ㅤCelticBible (@CelticBible) March 2, 2017
A shot so powerful it should have been followed by a shower of rain. Tommy Gemmell, RIP. pic.twitter.com/k2IaZ2n7SL— Alex O'Henley (@OHenleyAlex) March 2, 2017
"What will remain consistent, though, is the Celtic support and with those guys behind you anything is possible.”— CelticQuote (@CelticQuote) March 2, 2017
Tommy Gemmell pic.twitter.com/FlPnDoczAC
God bless you Tommy Gemmell 🙏🏻🍀 #Lisbonlion— Dylan McGeouch (@DMcGeouch) March 2, 2017