Adamson has made eight starts for Wednesday since the 2004/05 season with two appearances coming off the bench and has never really had a look in at Hillsborough.
No manager has never really shown much faith in the 28-year-old but he will be thrust into the firing line at Birmingham knowing that the club's previous custodian, Iain Turner, was undefeated in 11 games.
"Iain was outstanding," Bullen states about Turner, who has now returned to Everton. "There's nothing better for a defender when your goalkeeper is commanding and collects crosses the way he has done.
"Unfortunately he won't be with us for the last two games of the season but Chris Adamson has been outstanding in training, his attitude as a professional footballer has been absolutely exemplary and without doubt deserves his opportunity.
"It's just a wee bit unfortunate that there's going to be a bit of pressure on the lad now with the club undefeated in 11 games but I am sure he will handle it and we will protect him and hopefully help him pick up a couple of clean sheets."
Bullen meanwhile has been in fine form recently as the season draws to a close - many thought this would be his last season at Wednesday but his imperious form means he has deservedly been offered a new deal which he should sign soon.
He added: "I am delighted to have been offered a new contract because I always wanted to stay. We are chatting every couple of days, I'm not particularly difficult to deal with because I want to stay at the club and stay involved and it will not take much for me to sign the new contract."
Team news for The Blues game raises a few problems for Brian Laws - Adamson will come in for Turner, Deon Burton is set to miss out with an eye injury and Steve Watson was surprisingly recalled to West Brom yesterday.
So Marcus Tudgay will partner Steve MacLean up front with Jermaine Johnson coming back on the right-hand side while Kenny Lunt should come back in to midfield for Watson.