Chris Sharp scored twice as Hereford twice came from behind to beat Lincoln.
The visitors went ahead when Bulls defender James Musa nodded past his own keeper, but Stefan Stam's header drew the hosts level shortly afterwards.
Alan Power put the Imps back in front from the penalty spot after he had been fouled in the box by Kingsley James.
Sharp struck twice in five minutes to win it with a 25-yard drive and a tap-in, after Stam's shot was saved, before City's Peter Gilbert was sent off.
VIEW FROM THE DRESSING ROOM
Lincoln City manager David Holdsworth told BBC Radio Lincolnshire:
"Goals change games and they got back in, a little fortuitously I would say. I thought we played very well at times today but the goals came in quick succession.
"I thought we were the better side for the first half but you're looking for a little more maturity in certain areas and when they scored their second goal I think we lost our composure, they got the impetus and then scored the third goal.
"The maturity in the team will only come from learning from these occasions. Sometimes you have to suffer something like this to learn.
"We have to become more ruthless and harder to beat, our invention is good and we're scoring goals but we have to have more steel about us and a mental strength."