Northampton Town manager Chris Wilder has labelled the second goal his side conceded in their 2-1 defeat by Portsmouth as a "scandal".
Saturday's loss saw the Cobblers drop below Plymouth to second in League Two.
"There is no way they should score from our corner but we did not organise ourselves properly," Wilder told BBC Radio Northampton.
"I'm disappointed. I don't like losing at anything and the players don't, so they should be disappointed."
Prior to the defeat Northampton were unbeaten in 10 matches in all competitions and had won five consecutive league matches.
Despite being level on points with Argyle, Wilder bemoaned his side's ability to secure a draw against Pompey.
"I thought we were outstanding for the first 20-25 minutes but in the second half they were the better team for large parts," he said.
"We had weathered the storm and got a foothold in the game again and we looked as if we could win it so it is an absolute scandal that they scored from our corner.
"It is not being negative but we have to play cautiously in that period because without over committing it is a point for us and we move on.
"They have not had to work very hard for their goal and that is really disappointing."
Wilder said he was also disappointed for the fans after their biggest crowd of the season, 5,859, turned out.
"We have lost a big game of football in front of a capacity crowd and I take defeat tough," he added. "I am not looking at the league table and think it looks ok, the run had to come end.
"I am not having it, we have been beaten and we shouldn't have."