First, a quick look at the deal from Pittsburgh's perspective. Hinske is a solid veteran, and after a decent season playing every day in Tampa Bay last year was coming off the bench for the Pirates this year. In other words, Hinske was not a real integral piece to a team that about a month ago traded Nate McLouth, arguably the closest thing they had to a face of the franchise. Not surprisingly, the asking price was not high. Erickson has a nice ERA is low A, but opponents are hitting almost .300 off him. The other player in the deal, Eric Fryer, has an OPS of under .700 in high A. Both players are 23, so they are already are a bit old for the leagues they are playing in, especially considering their marginal success.
Undoubtedly, Hinske will be a backup for the Yankees also, but the real question is where. He can play first base, third base, left field, and right field. Yankees GM Brian Cashman was on record saying that he was not looking for a hitter because he wanted to see the team once OF Xavier Nady was back. However, it looks like he will miss the entire season now, so Hinske could be taking Nady's spot in the outfield. If that is the case, the Yankees will likely send Brett Gardner to AAA.
However, the Yankees are carrying a pair of light-hitting infielders, Cody Ransom and Ramiro Pena. They like Pena's glove, and he is young. Ransom is in his early 30s, and frankly at this point is more of a AAA infielder and emergency stopgap. I think it makes more sense for Hinske to take one of their spots on the roster, mostly because Brett Gardner is a better player than either Ransom or Pena right now. If that is the route the Yankees choose though, it will look like they sought out an upgrade to backup Alex Rodriguez. They just might have too, considering the added days they are giving him off, and the lackluster production of his reserves. Still, seeking out a better backup for A-Rod seems like something that the New York media would notice, to say the least.
We will just have to wait and see what the Yankees do.