Eyebrows were raised by some last summer when the Dutch great took the reins of what many expected to be a sinking ship.
Koeman, though, has been revelation in his first season in English football, not only steering Saints to calmer waters but new heights.
Only a point is needed to break the record Premier League points tally set last season under Mauricio Pochettino, who returns to St Mary's for the first time since leaving last summer when Tottenham arrive on Saturday.
The former Saints boss is unlikely to receive a particularly warm welcome at St Mary's after jumping ship - something Koeman has told fans he would not do this summer.
Asked this week at a Barclays Q&A event what he would do if Real Madrid came calling this summer, the Dutchman said: "Oh, Real Madrid? No, no, no
Not with Real Madrid
You can trust me."
When asked what he would say if former club Barcelona came calling, Koeman said laughing: "Oh, you make it more difficult
No, I stay.
"I am still young for the manager role
It is good to stay and to be the manager of Southampton.
"It is a very nice experience to be part of the Premier League
It is the best competition in the world and it is nice to be part of that."
Source : PA