Blues were 2-0 down at half time against the side ranked 120 places below them but managed a second half fighback to win 3-2.
“I thought they (Blyth) were absolutely brilliant and this is what the FA Cup is about, a team from down the non-league pyramid having a day like this," the Blues boss said after the match.
"I hoped our experience would tell and I didn't need to give them a rocket at half time.
“I didn't throw anything and I was quite placid because to be honest, the players gave themselves a rocket and you saw the result.
"We had a goal chalked off and Zigic missed a simple chance so you could argue we might have been two goals ahead, but their goals were good goals from their point of view."