Nathan Jones is desperate to bring in reinforcements in the winter window after losing all of his first four Premier League games as Southampton’s manager.
Rooted to the bottom of the league table, Southampton want to add some experience to their squad to give themselves a fighting chance of survival.
Orsic has been their target this month but earlier this week it appeared that a deal could be off and Everton joined the race to sign him.
But it has been claimed that an agreement is in place between Southampton and Dinamo Zagreb for the 30-year-old to move to St. Mary’s.
The Saints tabled an improved offer worth £6m plus add-ons and it was accepted by Dinamo Zagreb.
Southampton will now look to work out personal terms and put him through a medical as soon as possible.
Orsic was part of Croatia’s World Cup squad in Qatar and has a reputation for being a big-game player.
He has scored goals against Chelsea, Tottenham and West Ham in European competitions.