This year we have worked hard and I think the team spirit between us is very good. That unity is one of our major weapons.Geraldo Bajrami
They face a tall order to prevail over the two matches against a team who have won the competition for the last four years and have been described as 'probably the best young side in Europe' by Blues Coach Steve Spooner.
But that doesn't stop the Blues players trying to continue their enjoyable and entertaining FA Youth Cup journey.
Geraldo Bajrami, Blues Captain and centre-half, says: "It is going to be very tough, we know that.
"But nobody has got any fear. If we play against Chelsea like we have done in our previous games, hopefully we'll give them a good run for their money.
"This year we have worked hard and I think the team spirit between us is very good. That unity is one of our major weapons.
“Last year we had a good team, all the players were individually very good - but there wasn’t that team spirit we have this year.
“Everyone is just together, we back each other up and that’s why we’ve got a chance."
Blues met Chelsea in the Fourth Round last year and were beaten 5-0 at Solihull Moors.
Bajarmi recalls: "I don't think it was the best for us because we had Josh Martin injured, Joe Redmond got injured, we didn't have Ryan Stirk playing, who has been one of our main players this year. Ronan Hale could only play a half, Leo Brown got injured after only 10 minutes, so everything went downhill.
"I think this time if everyone stays injury-free and close together, maybe we've got a chance. The atmosphere all round us at the Club is really good and everyone is happy, so why not?".
Blues have been missing striker Brown due to injury and left-back Ryan Burke has also been sidelined of late.
Odin Bailey was named among the substitutes for the first time for Saturday's match against Ipswich Town, a testament to his ability and form that has so impressed Garry Monk.
He didn't travel to Bolton Wanderers last night due to a slight niggle picked up in training on Sunday.
A trademark of Blues performances in the cup and league - they have surged towards title contention in the PDL2 North over the past few weeks - is the style of their football, regardless of the stakes: possession-based, playing through the thirds.
Bajrami says that Blues know they also have to mix things up, and there are occasions where they will have to dig in, like during a testing 20-minute spell at half-time at Bury in the Fifth Round.
"A lot of credit should go to Steve Spooner and Karl Hooper," said Birmingham-born Bajrami, who joined Blues Academy at Under-14s after two previous unsuccessful trial spells when younger.
"From the start that's how they've taught us to play and it's a good thing. When we dominate games, teams start to tire out, gaps start opening up and we can play though them; especially in the second-half and we can get the killer goal that we need, like we did against Bury."
When Blues clinched their berth in the last four, amid bizarre scenes at a snowbound Carrow Road, with a 3-1 victory over Norwich City, there was a rightful sense of achievement for the Category Two Academy, who have only ever reached the Final once before, in 1967.
Bajrami reflected: "It's a good achievement for the Club, as well as the staff and players. I think we've got what we deserved. Over this past season we've been building and there's a good team spirit. Everyone is happy with each other and we're always laughing every day, but when it comes to the serious parts we do get serious in training and that and try to improve every day. When we came off that pitch and we knew we were in the Semi-Finals, not many people can say they've reached the last four of the FA Youth Cup."