Before we begin, let me define how I have compiled this list. By "breakthrough," I am referring to players who haven't yet reached their potential and are due for a coming-out party.
For example, I believe that Corey Webster and Steve Smith will have great seasons for Big Blue in '09, but they have already established themselves as star players.
Let me get it out of the way now, no rookies made the list. Throwing rookies into game situations right away isn't part of the Giants' philosophy.
While I do feel that rookie WR Hakeem Nicks could make an early impact, it is unlikely that he will put up big numbers in just his first year. After all, wide receiver is the hardest position (aside from QB) to adapt to in the NFL as a rookie.
So, without further ado, let's continue on to the list itself.