Perez, who replaced the injured Papiss Cisse at halftime, smashed home from close range at St James’ Park after defender Alberto Moreno failed to clear a loose ball in the box.
Perez also scored the winner when Newcastle won 2-1 at Tottenham Hotspur last week and his goal on Saturday was the highlight of an otherwise low key game of few chances from either side that only came to life in the closing stages.
Newcastle manager Alan Pardew, who has been vilified by their fans for the team’s faltering performances, told BT Sport he was surprised to see a friendly message written on a banner and recalled the words of the late Magpies manager Bobby Robson.
“This is Newcastle,” he said. “You have to know there are real highs, and as Bobby Robson said, the highs are massive here and the lows are equally as low.
“He needed a tin hat at times, I’ve needed a tin hat at times but when the good times come, this is as good a city to be in as any.”
It is certainly that at the moment for Pardew, whose side almost doubled their lead soon after scoring when Remy Cabella’s shot after a swift counter was saved by the outstretched leg of Simon Mignolet.
Although Liverpool had plenty of possession, they wasted most of it and Newcastle keeper Tim Krul was hardly troubled by an impotent Liverpool attack with just Mario Balotelli up front.
Balotelli almost missed the start of the second half after coming out late from the dressing room, and like most of his team mates, had an undistinguished game.
Liverpool coach Brendan Rodgers, whose team were held to a 0-0 draw at home by Hull City last week and needed two late goals to see off Swansea City in the Capital One (League) Cup on Tuesday, looked glum afterwards.
He refused to talk about Balotelli, but said the result was disappointing because Liverpool controlled much of the game.
“We did not create much in the final third and got punished for a mistake that has ended up costing us the game.
“We did not create as much as we would have liked. We have collectively lost as a team, I am not just going to talk about Mario.”
Newcastle failed to win any of their first seven league matches, but this was their third on the trot, after victories over Leicester City and Tottenham, and followed their midweek 2-0 win at Manchester City in the League Cup.
Newcastle, who were in the bottom three two weeks ago, rose to ninth on 13 points.
Liverpool remained seventh, just one point ahead of the Magpies who have now taken 10 points from their last four league games.
(Editing by Toby Davis)