Former UEFA president Lennart Johansson has died at the age of 89.
The Swedish Football Association said that Johansson died after a short illness.
The Swede headed UEFA from 1990 to 2007, and he is most recognised for founding the Champions League in 1992 - a development from what was previously known as the European Cup.
FIFA president Gianni Infantino led the tributes to Johansson.
"I am heartbroken by the news of the passing away of Lennart Johansson," Infantino said, in a statement on the FIFA website.
"He was a friend and an invaluable source of wisdom and inspiration.
"I will be forever grateful for having had him as the president of UEFA when I joined the organisation in 2000.
"Since then, Lennart has always been a role model of professionalism and, more importantly, of humanity."
Follow Denmark v Ireland via our live blog on RTÉ.ie/sport and the News Now app. Watch the match live on RTÉ2 or listen to national radio commentary on RTÉ 2fm's Game On.