Blackburn boss Sam Allardyce will have an operation on his heart this week and will be forced to miss the next three Premier League games.

The former Bolton boss was all set to lead Blackburn against his former club this weekend, and even addressed the media in the pre-game press conference yesterday.

Yet a shock announcement was made earlier today, and he will now go under the knife to have an angioplasty operation that, if succesful, will widen one of his coronary arteries.

Assistant boss Neil McDonald will take charge of Rovers for their next three games against Stoke, Fulham and Bolton but 'Big Sam' will be back in time for the Lancashire outfit's Carling Cup clash with Chelsea.

The Blackburn chairman John Williams confirmed that Allardyce was devastated to be missing out on today's fixture, but admitted that his health was the prime consideration for both him and his family.

"Sam is very disappointed, particularly at missing the Bolton fixture, but his well being is of prime consideration," Williams said.

"We all appreciate that Premier League football is a stressful business and prevention is always better than cure."