METAIRIE, La. -- There is plenty of reason for optimism that the New Orleans Saints can finally end their streak of three straight 7-9 seasons and make a playoff run this year.

But, man, the Max Unger injury news could take a lot of wind out of their sails.

Unger suffered a foot injury, a source confirmed, but the source said it is too early to determine if it will impact his status for the start of the regular season.

I haven’t put together my annual ranking of the Saints’ roster yet, but Unger was easily going to crack the top five (he ranked fifth last year).

Unger is essential to everything the Saints do so well in their elite passing game as a protector for Drew Brees up the middle. And he is key to the running game they have tried to revamp with the recent additions of Adrian Peterson and Alvin Kamara.

And just in case you didn't already value the impact a center can make, take a look at what Alex Mack did for the rival Atlanta Falcons last year as a game-changing free-agent signing.

Unger's power is obvious. But he also has plenty of athleticism in his 6-foot-5, 305-pound frame after beginning his career at Oregon as a left tackle.

And the Saints have long valued interior blockers for Brees, who loves to step up into the pocket and throw through passing lanes. Before they traded for Unger, the Saints had Pro Bowl guards like Jahri Evans, Carl Nicks and Ben Grubbs. This offseason, they ponied up $8.5 million per year for former Detroit Lions guard Larry Warford to replace Evans.

Unger, who was a two-time Pro Bowler for the Seattle Seahawks before being traded to the Saints in the stunning Jimmy Graham trade two years ago, has also quickly emerged as a leader in New Orleans. He was elected as a team captain last year and signed a three-year extension last summer worth more than $7 million per year.

There are a few silver linings, though. Unger isn’t expected to miss the entire season. So if the Saints can stay afloat early, Unger can still be part of a playoff push. Also, veteran backup Senio Kelemete could be a solid alternative after starting 14 games over the past two years (mostly at guard). Or perhaps second-year lineman Jack Allen could emerge this summer, assuming the Saints don’t look for help elsewhere.

The other good news is that New Orleans’ offensive line is pretty strong across the board after adding Warford and drafting Wisconsin’s Ryan Ramczyk with the No. 32 pick to compete with Zach Strief at right tackle. The Saints also have standout left tackle Terron Armstead, who should be a Pro Bowler himself if he can get past his nagging knee injuries, and still-improving left guard Andrus Peat, who was a first-round draft pick in 2015.

Make no mistake, though. While some of those things could help cushion the blow, this one still hurts.

It’s not a knockout punch. But count it as an early-round knockdown for a Saints team that has seemingly been fighting from against the ropes for three straight years now.