Pellegrino: Southampton didn't represent club values in Newcastle loss
The Saints were behind after 63 seconds at St James' Park as Kenedy scored his first Newcastle goal, his second coming just before the half hour to put the hosts in command.
And the points were secured in the 57th minute when Matt Ritchie made it 3-0, ensuring a result that keeps Southampton just a point above the bottom three with eight games to play.
"We are disappointed because from the first minute we were unfocused, we made this mistake, we pay the price the rest of the game," Pellegrino said.
"At this level you cannot start this way, you cannot make this mistake. We miss an amazing chance to try to improve. I've never seen my team this season competing this way without the spirit we need at this level.
"Sometimes you can play bad, sometimes you can make mistakes but you need to react with spirit, with character. We never could show this to our fans to our people, we have to say sorry to our fans because we never represent the values of the club today and in this situation we have to react as quick as we can."
FULL-TIME Newcastle 3-0 Southampton
Two for Kenedy, one for Ritchie and a vital three points for the Magpies who move up to 13th ⁰⁰#NEWSOU pic.twitter.com/GE6SfWT2F9
— Premier League (@premierleague) March 10, 2018
Newcastle's second goal came on a counter-attack from a Southampton corner and Pellegrino added: "We knew that Newcastle are really dangerous on the counter-attack, they are really solid, they don't concede too many. For this reason when we conceded this first goal it changed everything, obviously every single goal it was more difficult.
"We tried second half with the changes but we were never a threat for them.
"We need to change our spirit. Still we've got eight games, still we are alive. Football has this thing, when you lose everything looks worse, but in one week we've got another game, a massive game in the FA Cup, we have try our best to change our spirit on the pitch."
Matt Ritchie on a massive win for the Magpies. #NUFC pic.twitter.com/8XDeJ1L28D
— Newcastle United FC (@NUFC) March 10, 2018
Newcastle, by contrast, are five points above the bottom three, an easy victory easing the tension on Tyneside.
Manager Rafael Benitez has three weeks to prepare Newcastle for another crucial clash with Huddersfield Town game, their match with Tottenham next week postponed due to Spurs' involvement in the FA Cup, with international fixtures taking place the following week.
The Spaniard reserved special praise for Jonjo Shelvey, who set up two of Newcastle's goals, saying: "Really pleased for Jonjo Shelvey because he had the knee problem, he was pushing to play, even Kenedy had a little bit of a problem. Everybody was pushing, everybody wanted to be involved and it was a great effort, great result and a great game.
"[There are] still a lot of games to play but at least you know you can play this way and get points. We have confidence we can do it."
Of the extended break, he added: "We know that is not ideal but it's what we have. We have to manage these three weeks and try to be ready for the next game."