Messi won the award last year and had a prolific 2011-12 season, scoring 50 league goals. He was also top scorer in the Champions League for the fourth successive season with a record 14 goals.
His teammate Iniesta enjoyed another strong season at club and international level. He helped Spain defend its European Championship title at the European Championship, where he was voted player of the tournament.
Ronaldo scored 46 league goals for Real Madrid as it won its first La Liga title in four years. He also scored three times as Portugal captain at Euro 2012.
The winner will be announced on Aug. 30.
