LAFAYETTE — As coach Mark Hudspeth and his staff watched the film from Louisiana-Lafayette’s hearty defensive effort in their 19-9 win against South Alabama something dawned on them.

They might’ve played more players in that game than they had in any other game during their four years together in Lafayette.

“A lot of guys contributed Saturday night — more than we’ve probably ever played — and they contributed in a big way,” Hudspeth said. “That was great to see.”

Judging by the results, they might want to stick with that plan.

The Cajuns tightened the screws on the Jaguars in the second half, allowing just 150 yards while keeping them off the scoreboard.

Cajun defenders frequently rotated in and out of the contest, while South Alabama kept the same core group of players in the game. With fresh legs going up against tired legs, the results skewed in the Cajuns favor.

It makes sense to frequently rotate defensive linemen, who battle every play against an offensive lines that usually do not substitute. That is, if there are enough capable players on the defensive line.

“It’s a great system that we have substituting defensive linemen, because we’re deep,” said defensive tackle Jacoby Briscoe. “And we’re deep at every position on the defensive line, so if we can keep every defensive lineman fresh, that’ll mean we’ll be able to give 100 percent on every play.

And, as Briscoe pointed out, life in the trenches isn’t easy.

“It gets tiring running east and west, north and south,” Briscoe said. “Keeping a fresh set of defensive linemen on the side is a great thing.”

But it wasn’t just the defensive line getting a breather, the Cajuns swapped players out everywhere.

Perhaps no position group was the beneficiary of more consistent rest than the linebacker unit, which saw eight different players make a tackle last week.

“That does wonders, not only for us but for the defense,” said linebacker Kevin Fouquier, who saw extended playing time at outside linebacker for the first time since the Cajuns switched to predominantly using a four-man front. “I felt like I was able to put max effort.”

The same goes for outside linebacker Jake Molbert, a former starter whose senior season had been defined more by his injury than his impact on the field, who used his fresh legs to rack up a team-high seven tackles in the contest.

But for Molbert, it wasn’t only about the fresh legs. When players aren’t playing with their usual level of fatigue, they can better focus on the task at hand.

“When you’re in, you’re thinking more about what you have to do rather than, ‘Oh, I’m pretty tired, I’ve got to fight through this,’ ” Molbert said.

The Cajuns plan on substituting defenders liberally as the season goes on, but they understand they may face certain challenges in doing so. For instance: the team they play this week ran 100 plays from scrimmage last week.

When teams operate at a quick tempo, it makes substituting harder.

One way to do it is to rotate players at the same time as the offense, but that might not come in handy against the Aggies.

“They’re mostly what we call ’10 personnel,’” Hudspeth said. “They don’t substitute a lot. So we’ll only be able to substitute maybe when the ball is on the near hash or when there’s a stoppage in play. That will make it more of a challenge.”

Another way to do it is to use timeouts for defensive purposes rather than saving them for the offense. That’ll likely be the case Saturday in Las Cruces — Hudspeth said he usually goes into games giving the defense control of the timeouts in the first half.

However they get it done, after last week’s performance, the Cajuns intend to utilize their depth moving forward.

“I tell you … we flew around to the football,” Hudspeth said. “I think a lot of that may have had to do with guys being a little rested. We didn’t count on the same four guys chasing them around all night long. We were able to rotate some guys in and I think it paid off.”