WHITE SULPHUR SPRINGS, W.Va. (AP) The moment Saints safety Kenny Vaccaro saw a gap opening along the offensive line, he raced through it at full speed, slamming into the first offensive player who tried to block him.

Vaccaro knocked fullback Sione Houma off his feet and into ball carrier Tim Hightower, who was forced to change course. His momentum lost, Hightower was soon enveloped by the Saints' converging defense.

The play, which occurred during a training camp practice over the weekend, exemplified Vaccaro's description of what it's like to play for defensive coordinator Dennis Allen, who is trying to shore up a unit that was among the NFL's most porous last season.

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''His thing is, it's not about scheme. It's about the 11 players you put on that field and how fast you're playing,'' Vaccaro said.

''He always tells us, `The only advantage the defense has is fear. All the rules are skewed for the offense to have success, so if they don't fear you, you're not going to win.' So if you can fly around, you can play fast - with a scheme that everybody knows - you can be successful.''

The Saints ranked 31st in yards allowed last season with 413.4 per game, effectively cancelling out much of the production of New Orleans' second-ranked offense.

The Saints are hoping for better results with Allen, who coached the secondary on the Saints' 2009 championship team.

Technically, Allen is approaching what would be only his second full season as an NFL defensive coordinator. He left New Orleans for his first such post with Denver in 2011, then made an ill-fated decision to become Oakland's head coach in 2012.

He rejoined the Saints as a senior assistant after New Orleans had ranked second-to-last in defense in 2014, then took over as coordinator when Rob Ryan was fired 10 games into last season.

During his first full offseason in his current post, Allen has been simplifying New Orleans' defensive scheme.

He also has paid particular attention to organizational details such as substitutions and pre-snap alignment, which head coach Sean Payton repeatedly cited as one of his team's most glaring deficiencies last season.

''Half the battle is getting the call, getting your alignment ... knowing the call, and playing the defense,'' Payton said. ''That obviously has been an emphasis.''

Allen, who played safety in college at Texas A&M, articulates a clear vision for how he wants his unit to look on the field.

''We have total control over how fast we play and how hard we play,'' Allen said. ''There are going to be times where the offense is going to do some things that might dictate some different matchups; they might catch us in a bad situation. But how we get out of those situations is that we have 11 guys hustling to the football.

''It is really a philosophy and culture of how we are going to play and not as much of what (scheme) we are going to play,'' Allen added.

The Saints expect veteran middle linebacker James Laurinaitis, acquired as a free agent this offseason, to be an ideal fit to lead Allen's defense - not only because of his reputation for grasping defensive concepts and alignments, but also because he agrees that, for a defense, a psychological edge can be more important than a schematic advantage.

''A lot of times, it's more about your mentality as a defensive player and really as a unit than it is about Xs and Os,'' Laurinaitis said. ''Every play that the offense draws up is blocked for a touchdown. Every play that we draw up is supposed to be a tackle for a loss.

''This is all about, how can we play as fast as we can, as physically as we can,'' Laurinaitis added.

Now that Allen has simplified the Saints scheme, however, he expects his players to understand their assignments on both individually and holistically.

Third-year outside linebacker Kasim Edebali, whose five sacks ranked second on the club last season, explained Allen's approach this way: ''The last couple years, I was a young player, so I was very worried about my position and what I've got to do. But coach really preaches that everybody understands what's going on around you, so you really know where you are in the defense and where everybody else is, so you can play smart.''

Through the first five practices of training camp - three of them in full pads - the defense has come up with its share of highlights, from safety Roman Harper stripping running back Mark Ingram to a couple of interceptions of star quarterback Drew Brees. But the Saints' offense has produced some big plays as well during 11-on-11 drills.

Payton said after Monday's practice that it will take until the first couple of regular-season games to see whether the Saints' defense is meeting goals of being better at communicating, thwarting third-down plays and tightening inside its own 20.

But he added, ''I expect us to be, because it'll be hard not to be, right?''

Notes: Payton announced after practice that the Saints have signed veteran offensive lineman Tony Hills, who was with the club for part of last season, and assigned a waived-injured designation to rookie Ryker Mathews. ... The Saints have Tuesday off from practice and resume Wednesday.

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