Nigel Adkins has been dismissed as manager of Southampton and has been replaced by Mauricio Pochettino.
Adkins joined Southampton in September 2010 on a three-year contract when they were third from bottom in League One.
The former Scunthorpe coach guided them to back-to-back promotions, first to the Championship and then to the Premier League where they began the season with a 3-2 defeat at Manchester City.
However, they won plaudits for their enterprising approach, most recently in the 2-2 draw at Chelsea on Wednesday evening which saw them move three points clear of the relegation zone.
Pochettino, who left his role as Espanyol coach in November, will take charge for Monday's Sky Live home game with Everton.
Southampton executive chairman Nicola Cortese said: "This decision has been made with the long-term ambitions of Southampton Football Club in mind.
"Whilst we acknowledge the contribution Nigel has made during the past two years, for the club to progress and achieve our long-term targets a change was needed.
"Mauricio is a well-respected coach of substantial quality who has gained a reputation as an astute tactician and excellent man manager. I have every confidence that he will inspire our talented squad of players to perform at the highest possible level."
Pochettino added: "This is the kind of opportunity that any coach would relish. Southampton is a club with great heritage, and an even more exciting future.
"There is a clear vision to take the club to a new era of sustained success in the Premier League, and beyond, which I'm delighted to be part of."
Former Southampton captain Matt Le Tissier was not surprised to learn of Adkins' axe.
Le Tissier told Sky Sports News: "It doesn't surprise me. It's a strange time of the season, they've lost two of the last 12 games and came from 2-0 down to draw at Chelsea.
"(But) it seems to be the way the club's being run under the chairman. Nothing's surprising and it's a bit of a laughing stock."
The ex-England international did concede the timing shocked him - Saints have been in good form and are clear of relegation trouble at present - but added he felt this could have been on the cards for some time.
"I'm shocked at the timing, it's very strange and it's an odd thing to come to terms with today," he said.
"I think he had a bit of pressure early on this season, people thought it might happen then; maybe they couldn't get the man they wanted then. It's all very strange.
"I think everyone is taken aback by it all. They have come to terms with life in the Premier League, had a tough start and have turned things round pretty well."#
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Are Southampton right to sack manager Nigel Adkins?