NORMAN, Okla. -- It was a single play in a single game that signaled the imminent return of the Oklahoma defense to levels of its former glorious past.

With one minute to go in the Allstate Sugar Bowl, Sooner linebacker Eric Striker came barreling around the line. After beating left tackle Cyrus Kouandjio, who might be a first-round pick in the upcoming NFL draft, Striker leveled Alabama quarterback AJ McCarron and stripped the ball loose. Flying in from the other side, Sooner end Geneo Grissom scooped up the fumble and rumbled in for the game-clinching touchdown.

After several seasons of relative mediocrity, the Oklahoma defense finally rediscovered its swagger in that 45-31 Sugar Bowl win over the two-time defending national champs.

And buoyed by nine returning starters, several rising stars and one giant feather in a houndstooth cap, the Sooners have carried that swagger into the spring.

“The Sugar Bowl gave us a good boost,” said defensive end Charles Tapper, who was the only defensive underclassman to earn first-team All-Big 12 honors last year. “Knowing we kinda dominated Alabama’s offensive line, that the whole defense just dominated Alabama a little bit -- just a great way to come into the 2014 season.”

It wasn’t long ago the swagger of the Selmon Brothers and “Superman” Roy Williams and “The Boz” seemed lost forever.

The Sooners ended the 2012 season capitulating to Heisman winner Johnny Manziel, who humiliated them in the Cotton Bowl while becoming just the second player ever to rush and pass for more than 200 yards in a bowl game (Vince Young in the 2006 Rose Bowl was the other). The final month that season, Oklahoma couldn’t pressure the passer. Couldn’t stop the run. And couldn’t win without getting a half-a-hundred from its offense.

But thanks a scheme change from four to three down linemen last offseason that commanded a more blitz-oriented style, as well as a successful bid to bring Michigan defensive line coach Jerry Montgomery to Norman, the Sooners rapidly improved defensively last season despite playing several new starters.

Spurred by the emergence of underclassmen like Striker, Tapper and the Big 12 Defensive Freshman of the Year, linebacker Dominique Alexander, that improvement finally culminated in New Orleans.

The Sooners didn’t play perfectly against Alabama. But they sacked the Heisman runner-up seven times, and forced three turnovers that all led to Oklahoma touchdowns, capped with Grissom’s fumble return.

“As a team, things started to come together,” said coordinator Mike Stoops, who resuscitated the Sooner defense at the turn of the millennium 14 years ago and has done it again in the present in his second stint in Norman. “I think our team came together in that last game. That let us play with more confidence and swagger in the second half. Even when things got tough, I felt like our players were in control.”

With the return of almost all those players, the Sooners figure to storm into 2014 with one of the best defenses in the country.

Who knows, maybe the best.

Virtually the entire defensive line comes back, including Grissom and Tapper, who team up to give the Sooners a destructive duo off the edge.

Inside, Oklahoma will also welcome back Jordan Phillips, who was playing at an All-Big 12 level before suffering a season-ending back injury, and redshirt freshman Charles Walker, who has been turning heads for months during closed practices. During the winter, Walker ran the 40-yard dash in 4.67 seconds, shattering the Bob Stoops-era defensive tackle record at Oklahoma set by All-American Tommie Harris (4.80) in 2003.

“We’re starting to gain quality players in our backup positions that can play a lot of different places trying to earn their way onto the field,” Mike Stoops said.

That hasn’t just manifested along the defensive line, either.

Oklahoma’s entire linebacking corps returns, including Striker, who has become the Big 12 version of Lawrence Taylor. The secondary is brimming with young talent, too, led by cornerback Zack Sanchez, who intercepted McCarron in the Sugar Bowl to set up a late Oklahoma touchdown at the end of the first half and give the Sooners a 31-17 lead.

“We’re so far ahead from where we were last year,” Striker said. “We got chemistry with each other. We know how to play off each other.”

That’s a scary thought for the rest of the Big 12, and maybe all of college football.

Especially if Oklahoma can keep getting to the quarterback the way it did late last season. In their final four games, the Sooners sacked opposing quarterbacks 16 times. According to ESPN Stats & Info, South Alabama’s was the only FBS defense with more during the same stretch.

“We like to get to that quarterback,” Tapper said. “On third down, we let the dogs loose. Like the cops let the dogs loose to get them bad guys, we let the dogs loose on third down.”

Though it wasn’t a third down, that’s exactly what Oklahoma did to McCarron at the end of the Sugar Bowl.

The play won the game for the Sooners. While sending a message that defensive swagger is finally back at Oklahoma.

“I feel like this is going to be a big year for us,” Tapper said. “Dominating every team in the Big 12 and just all over the country.”