Southampton manager Ronald Koeman has stated they preyed on a Manchester United side that are under pressure.
New signing, Charlie Austin came off the bench to head in a 87th minute winner.
With United scoring just 12 times in 11 home games, Koeman looked to frustrate United at home and did just that.
“Of course, it’s a great win,” the Dutchman said. “It was a difficult game for both teams today. We knew they are under pressure.
“If you keep the organisation of your team during the game [United] will be nervous.
“Defensively we did a great job. Attacking-wise, in the first half we didn’t play well because we had some counter-attack movements and we didn’t create – maybe one chance from Sadio [Mane].
“We didn’t play well in that aspect of football but the rest was good enough to get a result in the game and until the end of the game we knew we had qualities in our set pieces and that made the difference.
“We did a great job, in our team organisation. We had great spirit, we had belief and that makes the 1-0 today.”
Koeman mentioned United’s set-piece frailties to Austin before the striker entered the fray and headed home James Ward-Prowse’s right-wing delivery.
He added: “I mentioned to Charlie when he came on the pitch – it was a corner or a free-kick, ‘go to the box, make a good header and it’s 1-0’.
“It wasn’t at that time but later on, yes [he scored]. That is why we wanted to sign Charlie Austin – great numbers of goals.
“He showed it in the last 10 or 15 minutes but it is not fair to talk about just one player because the team worked so hard.”