Diego, 27, has impressed in La Liga this season, but has not featured for his country since 2009, a statistic that he is keen to change.
"It is always a challenge, but Atletico Madrid are having a great season and I am completely focused. I am sure of that. If I continue playing as I am, I will get another chance," Diego told EFE.
Diego lifted the Copa America with Brazil in 2004 and 2007.