Blue's decision to represent the UK at this year's Eurovision Song Contest has been described by their former manager as"reckless insanity".
The four piece will perform the self-written song I Can at the annual competition, which will take place in May in Dusseldorf, Germany.
It is the first-time since 1997 that the UK has opted for an established act to represent the country at the event. On that occasion Katrina And The Waves triumphed with Love Shine A Light.
But Blue's former manager Daniel Glatman described the decision to enter the group as "reckless insanity".
He said: "They will have to win. Anything less and their reputation would be in tatters. It is the equivalent of Lewis Hamilton entering a go-kart race - he will be the strong favourite but there is also the possibility he could lose. So why risk it?"
Bookies suggested the UK entry stands only a slim chance of victory. William Hill list Blue as 25/1 outsiders.
Formed in 2000, Blue had a two-year hiatus before reforming in 2009. Over their decade long-career, the boy band has sold more than 13 million records, winning two Brit awards in the process.
A documentary following the four members of the band - Antony Costa, Duncan James, Lee Ryan and Simon Webbe - as they prepare for Eurovision is due to be filmed in the coming weeks and will be aired in April.
Announcing their Eurovision nod, Duncan said: "We're celebrating our 10 years together in 2011, so when the BBC approached us it seemed a great way to mark the occasion and also to be part of something which is still a British institution."
Simon added: "I've always wanted to represent my country, so this is a truly exciting experience for Blue."