According to the latest reports Saints have already sourced a replacement for Sadio Mane, but they will need to act fast before he signs a new contract with his current club.
The man that Ronald Koeman is allegedly tracking is Napoli's Dries Mertens.
Mertens is well known to Koeman as the Belgium international has spent a lot of his career in Holland most prominently with Utrecht and PSV before joining Napoli in Serie A for around 9.5 million euros in the summer of 2013.
A regular starter for Napoli in his three seasons he recently scored a second half hat trick in their 6-0 win over Bologna.
He has also played for Belgium, notably in the 2014 World Cup Finals he scored the late winner against Algeria.
Nowhe is about to enter the last year of his contract at Napoli and turning 29 on 6th May he has to decide whether to tie himself to the Italian club or seek a challenge elsewhere.
That challenge could be the Premier League and it could be Southampton.
He is being reported in the media as a replacement for Sadio Mane who is Manchester bound according to the reports, although no one can work out whether its City or United he will go to.
So Mertens could be a replacement for Mane or he could be coming in as an addition to the squad in his own right, certainly Ronald Koeman has been looking for a true winger for a while and as he showed when signing Pelle he is not afraid of signing a player in his late 20's.
Mertens could therefore fit the bill and would be available at a decent price given his age and the short time left on his contract.
Saints will have to act quickly though before Merten's puts pen to paper either at Napoli or elsewhere.