Tom Clarke’s 90th-minute header gave North End all three points to send Alex Neil’s men to within a point and a place of the Championship’s play-off places.
For Cardiff, this result followed reversals at the hands of Bolton and Fulham. The Bluebirds remain third, but have work to do if they are to stop what is a poor run of form.
“It’s a disappointing again but I can’t fault the effort. I can’t criticise the players too much because we’re so short and they’re doing the best they can,” Warnock said.
“We lost Craig Bryson and Joe Bennett before the game on top of the others we already have out and some of them have hit a brick wall now having given me everything.
“It’s a sloppy goal for us to concede and I thought the goalkeeper should have done better. But it’s a cruel game sometimes. When you see the number of lads missing you realise what we’re without.
“It’s down to me now. I’ve got to smarten it up, change things and make sure we don’t feel sorry for ourselves. We won’t get down and we’ll get on with it, but I’ve got to do something in the next few days to give the players a lift because it is difficult losing three on the trot.
“I have recommended to the board we sign two or three players and I hope they are supportive. We can’t sign five players in January, so we have to get guys fit and get on with it.”
The two teams delivered a woeful first period with few clear-cut chances.
After the break, both teams gambled in search of a winner but there was little between them until the last-minute drama.
Cardiff failed to clear a corner, the ball fell to Preston skipper Clarke inside the six-yard box, and the centre-half nodded home. Preston are unbeaten since November 4 and will hope to push towards the play-off places in 2018.
“We have shown this year, we can beat good footballing teams and we have also shown we can mix it with the physical teams,” Neil said.
“We knew what was coming. It was just a case of whether or not we could stand up to it. That’s twice we have now beaten Cardiff.
“This was not a game for the football purists. It was a rough, scrappy match.
“But I thought if there was any football being played it was by us. The substitutions made an impact and football is a squad game.”
England manager Gareth Southgate has claimed that the country needs to boot racism out of its own football before criticising World Cup hosts Russia.
Newcastle have been linked with a shock move for former Sunderland goalkeeper Simon Mignolet during the summer.