Free-agency review: Saints

Most significant signing: This one is obvious. The New Orleans Saints landed one of the top free agents on the market when they signed former Buffalo Bills safety Jairus Byrd to a six-year, $54 million contract. The Saints defense was already outstanding last year, but Byrd is a three-time Pro Bowler who specializes in creating turnovers from the center field position. That's the one element the Saints were really missing on defense last year. Their secondary has become one of the strongest units in the league -- following the blueprint of the Super Bowl champion Seattle Seahawks.

Most significant loss: New Orleans parted ways with several longtime veterans in a calculated effort to invest in younger players. But the decision to trade Darren Sproles to the Philadelphia Eagles was the most unexpected. Sproles has been a huge part of the Saints offense as a dynamic runner and receiver out of the backfield. However, it wasn't a complete shock since the Saints backfield is still very deep. And Sproles, 30, has seen his production start to dip a bit the past two years. The Saints received a fifth-round draft pick and cleared $3.5 million in cap space.

Biggest surprise: Byrd and Sproles were both a bit unexpected. But in general, the biggest surprise is that the Saints spent money so aggressively despite being slammed against the cap. They signed Byrd, re-signed right tackle Zach Strief (five years, $20.5 million) and kept running back Pierre Thomas with a two-year extension. All of those deals were cap-friendly in 2014, as the Saints continue with their win-now approach.

What's next? The Saints still have some holes to fill at center, receiver and cornerback. They may consider bringing back center Brian De La Puente or receiver Robert Meachem or finding a bargain-priced veteran at those spots in free agency. Or they could try to add depth through the draft. If they add any more free agents, they will need to carve out more cap space through restructured deals or player releases. The biggest issue this offseason will be working out a long-term contract for tight end Jimmy Graham, who is currently locked up by the franchise tag. That debate could linger well into the summer. But the Saints are already being charged more than $7 million against the cap for Graham's tag, so cap space won't be an issue.