Southampton manager Mauricio Pochettino paid tribute to his side, calling their win over Premier League champions Manchester City "incredible".
Saints won 3-1 at St Mary's
to move six points clear of the relegation zone.
The win was Pochettino's first victory as manager since
taking over from Nigel Adkins four games ago.
"I'm happy for all the people who work at Southampton and for all the people at St Mary's. It's been an incredible day," he told BBC Sport.
"I'm very happy with the players and the team who deserve the victory."
Jason Puncheon gave Saints the lead, following up to slot home after Jay Rodriguez's shot was saved.
Southampton's victory over Roberto Mancini's side was only the Saints' second success in 10 attempts at home to Manchester City
Steven Davis made it 2-0 after Joe Hart made a hash of Rickie Lambert's shot.
Edin Dzeko replied on the break but City's misery was complete when Gareth Barry inexplicably passed into his own net.
Pochettino said they always believed they could beat the champions and admitted the result would be a huge confidence boost in their attempts to stay up.
"The key was all the work we put in over the past few weeks," said the Argentine.
"The victory only comes if you believe you can get the victory and today we believed we could win and that is the way we should continue.
"It happened as we hoped, planned and wanted. Many times you can imagine and it is difficult to make it happen but today it went to plan."
He added: "The most important thing for me is we have two weeks to prepare for the next match and recover the players who were missing today.
"This result has a great value to us, the team deserved its victory. The added value of this victory is that we have shown we can play well and win matches."
The result also dents City's title challenge
the champions could slip 12 points behind leaders United on Sunday if they beat Everton.
And Pochettino joked Manchester United manager Sir Alex Ferguson might send him a gift as a way of thanks.
"If he (Ferguson) sends me a bottle of wine I will be very grateful, but he doesn't have to," he said.