Santiago Vergini to Sunderland: Black Cats Acquire Estudiantes Defender on Loan

Sunderland have announced their second signing of the winter transfer window after confirming that Estudiantes centre-back Santiago Vergini will spend the rest of the season on loan at the Stadium of Light.

The club's official Twitter account revealed that an agreement had been struck to bring the defender in on a temporary deal:

Vergini arrives as the second loan move of Sunderland's January window, three weeks after Marcos Alonso signed on identical terms from Fiorentina.   

The 25-year-old is a full Argentina international but hasn't appeared for his country since earning his first cap in September 2012.

Sky Sports' South American correspondent Paulo Freitas rates the defender in terms of positioning, but a lack of pace stands out as a potential weak spot:

Vergini comes to the club looking to further improve the Black Cats' fortunes since Gus Poyet took over, with the northeast outfit going through yet another stage of metamorphosis under the Uruguayan's command.

Speaking to the Sunderland Echo (h/t Sky Sports) earlier in the week, Poyet commended Vergini's desire to play for his team:

"If it goes through, we have to give plenty of credit to the player because he wants this badly. That gives you a big hope as a manager."

The defender has played a prominent role for Estudiantes in the Torneo Inicial this season, helping his side claim the joint-best defence in Argentina's top flight, conceding just 14 goals in their 19 games.

Vergini played the full 90 minutes for 17 of those fixtures, seven of which saw El Leon claim a clean sheet, according to Transfermarkt.

Sunderland are in need of patching up at the back, too, considering they've leaked the third-highest amount of goals in the Premier League this season (36), despite making a number of defensive signings over the summer.

Scott Heppell/Associated Press

Modibo Diakite and Valentin Roberge were both signed as free transfers to give extra options in the centre of defence, but have seen Wes Brown and John O'Shea claim most of the playing time when both fit and available.

However, Brown has shown some moments of weakness this term, and Poyet would appear intent to draft in some of his own options, with those signed under Paolo Di Canio's reign not quite living up to expectations. 

Vergini could be available for the Wednesday, Jan. 22, Capital One Cup semi-final second leg against Manchester United.