SAINTS have been given the green light to sign an Italian international colleague of Dani Osvaldo.

The club have previously shown interest in signing Cagliari centre half Davide Astori.

Boss Mauricio Pochettino shot down that rumour when asked about Astori back in November But now, as the transfer window re-opens tomorrow, Saints have been told to make an approach for the 26-year-old by Cagliari’s president.

The lack of real quality in depth in Saints’ central defence has been exposed in recent weeks following spells out of the side for first choices Dejan Lovren and Jose Fonte.

Jos Hooiveld has made a couple of high profile mistakes, leading to goals at Newcastle and at home to Tottenham - the latter ending up with his fourth Premier League own goal.

And Maya Yoshida also failed to make the most of his chance when he played in the 3-2 home loss to Aston Villa at the beginning of last month.

Indeed, Saints have not lost at home this season when Fonte and Lovren have lined up together.

Astori, 26, has been a regular for mid-table Cagliari in Serie A this season.

Cagliari president Massimo Cellino recently announced that star players such as Astori – and also Radja Nainggolan, who was also linked with Saints in 2012 – can leave.

Both players have been repeatedly linked with moves away from the Sardinian club.

Cellino is angry that Cagliari have been forced to keep large sections of their stadium closed because of ongoing safety issues.

“All the players are free to go; what the **** are they still doing in this lousy stadium,” he said before Christmas. “We play in a stadium worthy of Serie C.

“[Will Nainggolan leave in January?] No, he can leave in December, I tell you. He has six or seven clubs looking for him and I can’t keep hold of him again.

“It’s not an issue of money, as even if they give me less than his price tag, he’ll still go. If he doesn’t want to go, I’ll send him away.

“[Does that apply to Astori too?] It applies to everyone. I don’t rule anybody out.

“Anyone who wants to leave Cagliari is free to do so.”