Raiders general manager Reggie McKenzie tried to plug holes in last year’s leaky ship through free agency. It was a necessary exercise contrary to McKenzie’s draft-and-develop philosophy, given the roster depth overall. As is normal with veteran free agency, there were hits and misses. But, on a talent-thin roster, those misses cost the 2014 Raiders dearly. This year, McKenzie had a larger foundation thanks to talent acquired in recent drafts, but still had to heavily supplement in the free agent market. The Raiders missed out on coveted talent, but still acquired volume. Some players added depth, while others are on an island with great expectations...

The Raiders expect Latavius Murray to be the primary tailback, but Helu has a specific skill set tailor-made for coordinator Bill Musgrave’s offense. He’s an excellent third-down back with secure hands and toughness to gain yards after the catch. His signing was widely praised and, if he lives up to the hype, quarterback Derek Carr will have a dynamic safety valve to keep the chains moving.

Hudson was the team’s prize free agent after signing a five-year, $44.5 million contract with $20 million in guarantees. That’s a ton for a center, meaning Hudson must live up to his contract with excellent physical play and mental acumen. Early reviews are positive, but Hudson must be a force during the regular season to justify his paycheck. The Raiders can’t afford to waste those dollars on someone who isn’t excellent.

In this instance, production is important for player and team. Crabtree can earn significant bonuses with a big year, something he’s looking for after a disappointing free agent experience. The Raiders need the former 49er to realize his potential and become a reliable outlet for Carr. Crabtree may not be a speedster downfield threat, but he has excellent hands and must produce to divert attention from first-round pick Amari Cooper.

Lofton is an ironman and a tackling machine. That’ll be mandatory from a player charged with manning the heart of the defense without a safety net. Fifth-round pick Ben Heeney is Lofton’s only true backup at this stage, and the Raiders can’t afford for Lofton to miss many snaps. Lofton must be better in run defense behind tackles Dan Williams and Justin Ellis and keep gains minimal. Lofton must stay healthy and stay productive or the defense is in some trouble.

Allen signed a front-loaded four-year, $23 million contract with this offseason, a transaction that was met with skepticism following uneven performances with Philadelphia. The free safety can be a ball hawk and at time a liability on deep passes, but the Raiders need a consistent version to support young cornerbacks and allow Charles Woodson to play aggressive at strong safety. If Allen plays a solid center field, he’ll make everyone around him better. If he doesn’t, the Raiders defense could be vulnerable to the big play.