Heckingbottom could appreciate the quality of McLean’s set piece finish, but felt the free kick should never have been awarded after Mathias Kvistgaarden and Pelle Mattsson were felled in an aerial challenge with Jordan Thompson.
The Deepdale chief was also unimpressed by full-back, Odel Offiah, caught on his heels by Ali Ahmed for City’s opener.
“We’ve had a bright start, had the best chance of the game and then a lapse in concentration,” he said. “Odel is correct side, they take a shot; Odel is wrong side and we’re one down. It gets compounded by a referee decision. It doesn’t matter about whether it is our games, or games I watch on television, I am just really concerned what we think are free kicks these days.
“Jordan has jumped for the ball and won a header between two Norwich players and whether it is back arm or a little finger it is not even into the chest, not to the face, but two Norwich players go down holding their face. I don’t know what the rules are around officiating. I know they don’t, and it just compounded our error for the first goal.
“Kenny, we know, has top quality and has been a top player for many, many years, particularly down here. On Norwich’s side they will look and it and see they have a winger sniffing out a chance, and then quality on the free kick and those are the margins.”
Preston have now won one of their last 12 in the league to tumble down the table, but Heckingbottom rued some big second half chances spurned to make it a nervy finish for the Canaries.
“The big frustration is that we didn’t score. If we’d have taken any one of those chances we’d have made it much more difficult for Norwich,” he said. “We had chances second half, but we never made them feel that tension and anxiety that can come if we’d have got a goal.
“We have to get everything right and deliver top performances to give ourselves the best chance. Sometimes you can get away with those moments. We’re not at the minute, but that’s on us.
“You also need the other things to go your favour, like the referees and things like that, but then also we’ve got to be clinical. We can’t have those opportunities in and around the six-yard box of a good team away from home and not take them. After Norwich scored the first goal we allowed them to get control of the ball too easily.”