The Croatia youth international moved to La Dea as part of the deal that saw Ezequiel Schelotto join Inter.
"I am here to play more and I am happy to be at a great team like Atalanta," he told a Press conference.
"The President has convinced me that this is the right place, and has shown a lot of confidence in me.
"It was great being at Inter and training with superb players like Antonio Cassano and Samir Handanovic.
"The club have been a great help in my development."