Santiago Vergini
Sunderland closing in on Santiago Vergini, reports suggest.Reuters

Sunderland are set to confirm their second January signing after agreeing terms with Argentinian defender Santiago Vergini from Estudiantes de La Plata.

Vergini was identified as one of Barcelona's primary defensive targets during the summer, having played a key role for manager Gerardo Martino during his tenure at Newell's Old Boys where he led the Argetinian side to the domestic league title.

Eventually the defender moved to Estudiantes de la Plata but according to many Argentinian media outlets just five months later he is set to join Premier League strugglers Sunderland.

The Black Cats have already agreed terms with the centre-back and reports suggest that the deal may be concluded today after Sunderland agreed to pay Vergini's £400,000 release clause to Estudiantes.

The 25-year-old will sign an 18-month deal, becoming the second Sunderland January signing after Marcos Alonso, who joined last week from Fiorentina on loan until the end of the season.

Estudiantes president Enrique Lombardi confirmed that Vergini will leave the club soon although he did not confirm his destination.

"He wants to leave Estudiantes, and as he isn't a player that is considered as principle in the squad, we have accepted his departure," Lombardi said.

"He wants to change team, and as there is a good offer that we have analysed, he will leave our club."

Sunderland boss Gustavo Poyet is desperately searching for January additions to avoid the relegation to the Championship. The Black Cats are currently at the bottom of the Premier League but they are close to the Capital One Cup´s final, after beating Manchester United 2-1 in the first leg of the semi-final.