Blues had led the game 1-0 courtesy of a Peter Lovenkrand's goal in first half stoppage-time but Ben Marshall equalised to earn the Foxes a point four minutes from the end of normal time.
"I was pleased with the performance but disappointed to concede a late equaliser four minutes from the end," the Blues boss said after the 1-1 draw at St Andrews.
"My players showed a lot of passion, desire, drive and energy and I was hoping they could hold out, but unfortunately it was not to be.
"I thought it was a cracking game by both teams."