The 21-year-old started his footballing career with the Rams at the age of 11 so walking out at Pride Park this weekend will be a proud moment for the Derby-born 'keeper.
"Going back and playing will be brilliant," admitted Kean. "I was there earlier in the season when we got the draw, but I was on the bench then, so to go back and play will be something different for me.
"It will be an experience for me with all my family being there and I'm really looking forward to it.
"I was there from the age of 11-18 and apart from the last couple of days I've only fond memories of my time at Derby, I'd like to thank all coaches that I played under and all the friends I have made.
"Some of the boys that I played with in the youth team are still there in the first team so I've got really good memories."
Despite divided loyalties, Kean knows that Saturday is all about qualifying for the 5th round of the competition, and against fellow npower Championship opposition he feels Rovers have a real chance.
"The most important thing is to get through to the next round of the cup," added Kean.
"Both sides will see it as a chance of progressing against a Championship rival.
"Good cup runs can help your league form so hopefully we'll see it as a way of doing that.
"The priority is obviously the league but if you can have a good cup run and then take that form into the league then that would be great."
Tickets for the Derby clash will be on sale at Ewood Park until 4pm Friday. They will be on sale on the day from 12pm on Saturday from the South Stand Away Ticket Office.