Yep. That's the inconvenient truth. 28 year old CB coming off a very serious knee injury. I think he'll be better next season, but I don't think he'll be anything like the shutdown corner he was close to being a couple years ago.
In defense of Beane: this is what happens when your team is good. Based in part on cap considerations, you sign guys to extended contracts in which the team gets excess value in the early years, and the player gets seriously overpaid in the latter/decline years.