Danny Simpson says Leicester are struggling to get to grips with the Premier League crackdown on set-piece defending.
Officials are under orders to penalise the kind of shirt-tugging and blocking that for years went largely unpunished.
And Simpson admits the new rules are having an impact on the champions’ experienced defenders, who could not prevent Manchester United scoring three goals from corners during Saturday’s 4-1 defeat at Old Trafford.
“Err, I have to be careful what I say,” he said. “It is in your mind, yes, we have seen a few decisions this season. It is in your mind.
“It is something we have to learn to adapt to as players. They have changed the rules.
“The way it was last season, I thought we were very good at defending set-pieces and we made it tough for the opponents.
“You have been doing that for all your career and suddenly you have got to change it, but it’s the same for everyone, it’s something we have got to work on and look at.”