Ronald Koeman will have to fight his way out of Saints if he wants to take over at Everton.

The Dutchman has been the subject of intense speculation linking him with the vacant post at Goodison Park, and a potential salary of £7m-a-year.

The Daily Echo understands that Everton have contacted Saints for permission to speak with Koeman, an essential move if any deal were to occur.

For their part, Saints are believed to have not yet granted permission and are determined to do everything they can to hold on to Koeman, who has been a great success in his two seasons in charge.

The contract extension they have tabled for Koeman – who has one year remaining on his existing deal – would comfortably make him the highest paid manager in the club’s history.

Negotiations over the new contract started immediately after the end of last season and were overwhelmingly positive, with an expectation that Koeman would sign after he returned from his holiday in the Caribbean this week.

However, having changed agent things have gone quiet on that front, with a constant stream of stories linking Koeman with Everton coming out in the media in the meantime.

It now seems Everton have made Koeman their top target, but Saints will have to give permission if the boss is to speak to Everton.

With a year left on Koeman’s contract still, Saints continue to hold the aces.

It will have to be on Koeman to force his way out if he were to go.

He has continually said that he will, at the very least, see out the remaining year on his contract at St Mary’s.

Saints expect him to honour that, while also hoping that he will sign to stay far longer.

Koeman will, therefore, actively have to go out of his way to get out of Saints.

Only if that happens and the situation looked utterly futile would Saints the start the fight for the maximum level of compensation.

There is still a chance that it won’t come to that, and that Saints can finalise a new contract with Koeman, even if the finer details alter a little to persuade him to stay.

Everton's approach does, though, leave this under threat.

Koeman was understood to have been impressed with the ambitious plans for the future presented to him by Les Reed, which include qualification for the Champions League in the foreseeable future.

It was his belief in the Saints plans that prompted the contract negotiations, which the Daily Echo understands were positive throughout.

Should Koeman decide he wants to go to Everton, it would likely be a money driven move.

That would either be personally, as the reported £7m-a-year salary would make him the sixth highest paid manager in the world, or in terms of the spending power he would have at his disposal to try and return Everton to the upper echelons of the Premier League.

Everton’s new billionaire backer is said to be prepared to pledge £100m for a transfer kitty this summer, along with any funds raised if Romelu Lukaku or John Stones move on.

Koeman will not have that kind of cash at his disposal at Saints, but has previously insisted he enjoys working the way he has at St Mary’s, spending plenty enough still to develop his squad and enjoy continual progression.

Saints can also offer European football, with Koeman having guided them straight into the Europa League group stages with the club still very much hoping he is in charge when those fixtures start.