No way Diggs sees year 3 of this contract. He'll be 32 next season and coming off an ACL injury. Most WRs, even when healthy, tend to take a nose dive in their performance after 32.
With how much cap space they have, I'd imagine this deal is frontloaded and they can even maybe even move away from him after one season without really taking a hit.
Also, who the hell were the Pats competing against for them to give him that much? Seems like the market was ice cold for Allen, Cooper, and Diggs, and then this bomb came out of nowhere.