There has been very little transfer talk on Wearside so far, with everybody's mind far more focused on the crucial task of appointing a new manager following Dick Advocaat's decision to retire. But, given Sunderland's many deficiencies across several areas of the squad, one eye should certainly be kept upon bringing new blood in for the 2015/16 Premier League season. The upcoming Copa America tournament could be an invaluable place to scout potential recruits. Although likely to be dominated by major stars such as Lionel Messi, Alexis Sanchez and Neymar, the tournament is sure to throw a few lesser-known faces into contention for the summer transfer window. On the whole, South and Central American teams had a very successful World Cup last year, proving once again the depth of footballing talent in that part of the world. Such teams are often characterised by attacking flair and creativity, but teams such as Chile, Colombia and Mexico couldn't have exceeded expectations as they did without a great deal of defensive grit and tactical nous to go with it. The tournament begins on June 11th and runs through to the final on July 4th; let's hope Sunderland's scouting team keep tabs on all the goings on. It could prove vital for their survival and growth next year. Here are ten players that could change the fortunes of their national sides, and potentially the Black Cats too.