The Taoiseach has led tributes to Tyrone senior football star Cormac McAnallen (24), who died suddenly this morning.
Mr McAnallen, who won All-Ireland honours with his county last September, died after taking ill at his home. The cause of death is unknown.
Cormac McAnallen playing against Down in St Tighearnach's Park, Clones, Co Monaghan last July
Mr Ahern has extended his sympathies to the McAnallen family. He said: "I met Cormac recently and he was a wonderful young man. He will be deeply missed by his family, his friends and his sport."
"On behalf of myself and my colleagues in Government, I would like to extend our deepest sympathies to his fiancée, his family, his team mates and the people of Tyrone at this most difficult time."
The player has led the Tyrone side in recent games as regular captain, Peter Canavan, is injured. He captained Tyrone to victory in the Dr McKenna Cup just last month.
Mr McAnallen also won All-Ireland medals at minor and under-21 level and represented Ireland in last year's International Rules series in Australia. He was named on the prestigious All Star team of 2003 and worked as a teacher in Co Armagh.
Speaking to RTÉRadio this morning, an emotional Tyrone manager Mr Mickey Harte said: "He will be so much missed. I got the news during the night and it's just unbelievable.
"He was a real friend and gentleman. People talk about role models and they misuse the word. If you look for a real role model, then you look no further than Cormac McAnallen.
"There was so much about him that was so good. A leader, and at just 24 he had achieved everything that you could achieve in football . . . he was such a gentleman and such a dedicated guy," Mr Harte said. "It's a sad day for football and sport."
GAA President Mr Seán Kelly said: "Cormac exemplified everything that was good in a gaelic footballer and human being. He had that great and rare gift of greatness, allied to humility.
"Cormac's achievements, his modesty and unassuming nature endeared him to everybody and would be a monument to his memory forever."
Mr. Liam Mulvihill, Director General of the GAA, said no words could describe the shock and sadness he felt on hearing the news. He said members of the GAA community, both here and abroad, shared in the McAnallen family's grief and that their thoughts are with them at this time.
The Minister for Arts, Sport and Tourism, Mr John O'Donoghue, said: "It is with great shock and sadness that I learned this morning of the untimely death of Cormac McAnallen."
"He was a great footballer and captain and was an outstanding role model for all sportspeople. His death at such a young age is a monumental loss to his club, his county and to gaelic football. To his family and his Tyrone teammates I extend my deepest sympathy on their great loss."
The Gaelic Players Association (GPA) said McAnallen's influence and achievement throughout his playing-career was "consistently brilliant".
"His commanding competitive presence and his friendship off the field will be sorely missed by all who had the good fortune to cross his path in life," the GPA said.
As a mark of respect, the GAA has postponed Tyrone's National Football League Division 1A game with Cork in Omagh on Sunday. A minute's silence will be observed at all NFL games this weekend.