Southern University quarterback Austin Howard (7) fields the snap before throwing a touchdown pass to running back Jarmarqueza Mims in the first half of the Jaguars' game against the Wildcats, Saturday, Sept. 30, 2017 at A.W. Mumford Stadium.

On the second play of the first drive of Southern’s 37-31 win against Prairie View on Saturday, quarterback Austin Howard made the first of many snap decisions of the day.

The play call was a run-pass option — RPO, in football parlance. Howard’s task was to read the second level of the defense on this particular play, both before and after the snap, and, as he held the ball out to starting running back Herb Edwards, decide whether he would let go or pull the ball back and throw.

With Southern’s offensive linemen surging forward to run block, the linebacker crashed. Howard pulled and fired a dart to Dillon Beard that resulted in a 37-yard gain.

Two plays later, Southern made the same play call. Again, Howard threw the ball to Beard, who was occupying the area vacated by the linebacker. This time, it was a 31-yard touchdown.

“If a 'backer gets out of the gap he’s supposed to be in, you replace him,” Beard said. “That’s how offense is: Go where the defense is not.”

RPOs have been a successful staple of Southern’s offense under offensive coordinator Chennis Berry. With the added benefit of a four-year starter at quarterback, they are especially lethal.

“It’s a split-second (decision),” Howard said. “It happens very fast. But I’ve been running this offense for four years now; I’m comfortable with it.”

The premise is relatively simple. As the name suggests, the play can either result as a run or a pass, depending on the quarterback’s read. As center Jaylon Brinson put it, “We just do our job.”

On RPO plays, the offensive line blocks as if for a run play. The running back acts the same, crashing toward the hole with purpose. The receivers and tight ends run routes as if it will be a pass play.

The play is most successful when Southern is running the ball effectively.

“Our whole pyramid, you look at who we are offensively, it starts with the run game,” Berry said. “You have to be able to run the football. To have the ability — whether it be play action or whether it be a run-pass option — that gives us balance.”

Whether it is a run or pass depends on the quarterback’s read. Each play call designates his read to be based on the defensive line (first level), linebacker (second level) or safety (third level).

Provided a team has a quarterback who can make the proper read, it stresses a defense to defend both the run and the pass on the same play.

“It challenges you because you’re trying to stop the run, yet we’re throwing the ball off run looks,” said Southern coach Dawson Odums. “That’s the biggest challenge for defenses across the board.”

The process of making the proper read starts in the film room during the week — and Howard often has a good idea before the play starts whether he will pull the ball and throw or hand it off to the running back.

“I can make (the decision) before the ball is snapped,” Howard said. “That just comes with watching film. You know if he’s lined up in a certain way … you can play faster if you know what he’s going to do when he’s in a certain position.”

Follow Luke Johnson on Twitter, @ByLukeJohnson.