Southampton chiefs have reportedly been left upset by the manner in which Ronald Koeman has gone about instigating a move to Premier League rivals Everton.
The Dutchman is expected to swap St Mary's for Goodison Park early next week after holding talks with the managerless Toffees.
According to The Sun, Koeman and his representatives opened discussions with Everton - without a head coach since sacking Roberto Martinez last month - prior to Southampton giving their boss of two years permission to do so.
In a bizarre twist, the same report suggests that Martinez could now be brought to the south coast to replace Koeman, although the Saints risk losing a number of key players.
It is claimed that Jordy Clasie, Sadio Mane and Fraser Forster will all seek moves away from the club should Koeman depart, with the latter a target for the Merseyside outfit as they seek to replace Tim Howard.
Southampton finished the 2015-16 Premier League season in sixth place, while Everton endured a disappointing campaign as they finished down in 11th under Martinez.
