Rotherham boss Steve Evans believes the signing of Tom Thorpe is a real coup.
But reports suggest Taider may not be the only Inter playing arriving at St Mary's, with Ezequiel Schelotto and Hugo Campagnaro strongly linked with Southampton.
Koeman has, however, revealed that Taider is arriving.
"We are looking for the best for Osvaldo and the best for the club," Koeman said.
"Taider brings quality and we need that. We need competition in the squad as well and that will be good."
Koeman is looking to bolster his squad after seeing Rickie Lambert, Luke Shaw, Adam Lallana, Dejan Lovren and Calum Chambers all leave Southampton this summer.
So far the Dutchman has brought in Graziano Pelle, Dusan Tadic and Ryan Bertrand.