Jay Rodriguez gave the home side the lead on the stroke of half-time at St Mary’s before Rickie Lambert made it 2-0 shortly after the break.
Adam Lallana then made it three with a superb 25-yard effort in the 70th minute, before Rodriguez’s second of the afternoon wrapped up a dominant win late on.
It was a tough day, a really tough day
“It was miserable for us,” Pardew told BBC Sport. “We were second-best today and looked like we had no energy.
“It wasn’t us today and we have to do a lot of work to get ready for Manchester United next weekend because that wasn’t good enough for Newcastle.
“We lost the battle almost everywhere on the pitch. It was a tough day, a really tough day. For all our fans, I’m afraid that’s not good enough. I’ve made it clear to players we have a lot of work to do.”
Meanwhile, Mauricio Pocettino, whose side leapfrogged the Magpies up into eighth place, was thrilled with a “fully deserved” victory.
“We had a brilliant first half and nullified Newcastle,” said Pochettino. “We had total control and dominated the entire game.
“If you look at the amount of chances we created, it could have finished 5-0 or 6-0. It was a fully deserved win.”
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