Claude Puel has suggested a deal for Martin Caceres could happen this week
Martin Caceres is a free agent having been released by Juventus last summer, meaning he can be signed outside of the transfer window.
The centre-back had reportedly turned down the Black Cats in favour of a move to St Mary's and is said to have undergone a medical.
Martin Caceres has been a free agent since last summer
And Saints boss Claude Puel has hinted something could happen regarding the defender by the end of the week.
When asked about the Uruguay international, Puel said: "Caceres is not with us. We will see what happens in the next few days."
Southampton are in need of defensive reinforcements after Jose Fonte joined West Ham last month and Virgil van Dijk picked up an injury.
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Caceres has reportedly already seen a move to AC Milan fall through as the Italian club could not match his wage demands.
The Serie A side are said to have offered him a £4,000-a-week basic contract with a pay-per-play bonus of £21,000 a game which was not enough.
If Caceres does make the move to St Mary's he would link up with former Juve team-mate Manolo Gabbiadini who joined Saints last month for £14million.