Sunderland manager Roy Keane claims he "will not tolerate" abuse from supporters.
Keane was booed by some fans as his side struggled to overcome Northampton in the Carling Cup on Tuesday night.
The Black Cats needed penalties to see off the League One side and Keane labelled the night as one of the worst in his career.
The former Manchester United midfielder was furious with his players' performance but was also disappointed to be subjected to crowd abuse.
"I won't tolerate people abusing me, absolutely none whatsoever," Keane said. "Some people were targeting me and that's something I've not come into the job to accept again.
"I appreciate criticism, constructive criticism, which I'm going to receive.
"Trust me, my biggest critic is myself. I got my team definitely wrong. I should have gone with one or two younger players but I can do that in the next round.
"The abuse, I know it is part of football, but that is something I won't tolerate."