Saints manager Ronald Koeman admits his side have got the belief and are not scared to compete with the bigger clubs in the Premier League after they secured a 1-0 win at Old Trafford.
Dusan Tadic came off the bench to score the winning goal for the Saints in the second half and the three points secured over Louis van Gaal's team sent Southampton to third position in the Premier League table [dropping United to fourth].
Southampton have been really impressive this season and have continued their fine form after taking seven points from meetings with Chelsea, Arsenal and United in recent weeks.
And Dutch boss Koeman says his team fear no one as they fight to secure a Champions League spot.
"We defended well and the spirit was unbelievable from the players, [we were] a little bit lucky but remember the [reverse] game, Man United was the lucky one," he said, regarding Man United's 2-1 win at St Mary's Stadium in December.
"Maybe we are [lucky] but if you finally win you deserve to win because I think it's a compliment to the players how they play.
"I said before we could make it very difficult for them and we did. We know we have a strong team and that was important at the end of December.
"We got a point off Chelsea, the three points against Arsenal, it makes for good belief among the players. That's always what you need if you are not a big club and you have to play a big one.
"We are not afraid of the name, or the stadium. I think we learned that in the last few weeks."
Written by @Chukkymufc