Michael Laudrup was frustrated after Swansea City copped an injury-time equaliser for the third time in four matches on Sunday.
The Jacks were held to a 3-3 draw by Stoke City at the Liberty Stadium when the visiting side were awarded a penalty for an apparent handball on Wayne Routledge.
Charlie Adam stepped up to send the 96th minute spot kick past Gerhard Tremmel, leaving Laudrup to rue a very questionable decision from referee Robert Madley.
"I'm so frustrated. We have experience that teams score against us in injury time," he told Sky Sports.
"What is incredible there is always opinion about 'is it a penalty, it is not a penalty' but how on earth can you explain that seven Stoke players inside (the box), none of them are asking for the penalty and still the referee gives it, in the 94th minute.
"I don't have words.....it's really incredible.
"Sometimes I just wish that those referees or linesmen, they could come out and say 'Sorry, I made a mistake'.
"(That would be) no problem, we are all humans - I make mistakes, you make mistakes, the players make mistakes - but why can't the referees say sorry?"
It was the third match in recent times where Swansea had been denied all three points by a late leveller following two 1-1 draws with Kuban Krasnodar in the Europa League.
