Tommy Miller 'knicked a point' for the visitors with an equaliser 21 minutes from time.
"We nicked a point, no doubt about it," Royle said after the 1-1 draw.
"I was trying to remember our second attack of the game. Preston were excellent and swarmed all over us.
"In the second half we did improve but the only good thing at half time was that it was only 1-0.
"I played a shock tactic from the start of the second half, using two substitutes but it was nearly three substitutes.
"James Scowcroft got a knock to his calf but was excellent and the referee will think again about the booking."