The New York Yankees needed a frontline starting pitcher, both to address the depth problems in their rotation and to cover the possibility that CC Sabathia's 2013 is a sign that he's no longer a true No. 1 starter. The market this offseason offered only one pitcher who might be able to fill that hole for the Yankees, Masahiro Tanaka, so while interest in him was broad across MLB, it's no surprise that he ended up with a team that had both the need and one of the majors' two largest revenue bases to tap into.
Darvish not a good comparison
Tanaka isn't Yu Darvish, an unfair comparison based more on their country of origin than their stuff or builds.