Steve Spagnuolo proved in St. Louis that he was overmatched as a head coach but there’s no denying that he’s one hell of a defensive coordinator. That’s why the New Orleans Saints did well to replace Gregg Williams with Spagnuolo when their coordinator position became open last January.

But do the Saints have enough pieces on defense to make Spagnuolo’s scheme work?

Make no mistake, Spagnuolo’s defense has more depth, is more creative, and is more versatile than the one Williams developed over his three-plus decades of coaching. Spags is a disciple of the late Jim Johnson, who was a blitz-happy playcaller but he also played with discipline on the backend.

That’s why New Orleans fans should take comfort in the fact that Spagnuolo will keep the Saints aggressive while also implementing more zone coverage in the secondary. Instead of almost irresponsibly blitzing defenders like Williams, Spags will bring a more calculated approach to his play designs.

That said, you have to wonder whether or not Spagunolo has enough to work with. Leading pass rusher Will Smith has been suspended four games for his role in the team’s bounty scandal and Curtis Lofton, one of the Saints’ free agent signings this offseason, doesn’t have the same coverage skills as Jonathan Vilma (suspended for an entire year).

Can the Saints generate enough pressure with their front four in order for Spags’ defense to be effective? Safety Roman Harper recorded nine sacks last season but if Spagnuolo plans to run a lot of zone, Harper will likely remain in coverage. Junior Galette finished with four sacks last season but he’s only a situational pass rusher and Sedrick Ellis has been a major disappointment since the team selected him with the seventh overall pick in the 2008 draft.

The Rams weren’t very good under Spagnuolo the past three years but one thing they could do was get after the quarterback. Chris Long finished with 13 sacks last season while James Hall and Robert Quinn each had six apiece.

But all three of those players were able to rush the quarterback starting with their hand in the dirt, just like Osi Umenyiora, Michael Strahan and Justin Tuck were able to do while Spags was the defensive coordinator in New York. His schemes work best when the front four is able to generate pressure on its own, which is why he potentially has a problem in New Orleans.

While Williams was able to generate pressure from the secondary, that’s not the way Spagnuolo runs his defense. The Saints simply lack that premier pass rusher and unless 2011 first-round pick Cam Jordan is ready to take the next step in his development, New Orleans could struggle in Spags’ first season as DC.

That’s not to say that Spagnuolo isn’t creative enough to find other avenues to get after the quarterback but Saint fans may have to exercise patience when it comes to their new defensive coordinator. He was an excellent hire but every coach needs the pieces in order for their scheme to work.