It’s no secret Lincoln Riley is fond of the “side eyes” emoji. Oklahoma’s coach posts them on Twitter on the cusp of big recruiting news.

His inaugural season will draw plenty of eyes.

From changes in defense, to critical vacancies on both sides of the ball, to Riley’s coaching style, there is much to monitor.

Here are five things to watch:

1. The 4-3 switch: Those frustrated with the Sooner defense’s performances against Big 12 passing offenses will be treated to a change. Success is not guaranteed, but change is clearly coming.

OU is operating primarily from a base 4-3 alignment, which consists of four down linemen and three linebackers, ideally creating a more effective pass rush.

The Sooners won’t totally abandon the 3-4 scheme they’ve used since 2013. Expect to see both looks.

• Watch this: How does the defensive line, specifically tackles Neville Gallimore and Matt Romar, benefit from the extra one-on-one assignments at the line of scrimmage?

2. Generation ‘Next’ RBs: The last time OU entered September without a proven running back was 2014, when Samaje Perine soothed all fears with a 1,745-yard freshman season.

The Sooners are confident they can produce a quality run game behind what’s largely considered one of the nation’s top offensive lines, if not the best.

Still, who runs the ball matters.

“Oh, it matters,” Riley confirmed.

Redshirt sophomore Rodney Anderson, sophomore Abdul Adams, junior Marcelias Sutton and freshman Trey Sermon will all carry the ball in the Sept. 2 opener against UTEP. Only one of them — Adams — has more than one carry at OU and as a group they’ve produced 297 yards at the Division I level.

• Watch this: Carrying the ball is one thing. Watch how this group catches the ball and blocks. Those were two strengths of their predecessors, Perine and Joe Mixon.

3. Backing up Bake: Much of the offensive success is predicated on quarterback Baker Mayfield staying healthy. With a band of new playmakers, his ability to remain on the field and distribute to them is critical.

Mayfield hasn’t missed a start in 26 games at OU. Should that change, Kyler Murray or Austin Kendall will be asked to keep Riley’s first season as head coach afloat. A backup has not been named and likely won’t be until the opener.

• Watch this: There’s another reason the backup role matters. It’s pure speculation, but if Kendall is named QB No. 2, Murray could see time in another offensive role, likely receiver, if OU needs an additional playmaker. Murray is considered the team’s fastest player.

4. On the receiving end: Nearly identical to the running back situation, this can’t be overemphasized.

The Sooners’ ability to plug-in new athletes and move on is a lot like one of defensive line coach Ruffin McNeill’s favorite acronyms: F.I.D.O, which stands for “Forget It and Drive On.”

There may be talent, but there are no proven commodities in this receiving group beyond Kentucky graduate transfer Jeff Badet. The rest consist of freshmen, junior college standouts or Sooner veterans eyeing breakthroughs.

• Watch this: Watch the first four games with patience. That’s how long it took last season before Dede Westbrook hit his historic run of 907 yards receiving in a five-game stretch. OU might need time to find a go-to target.

5. Riley’s reign: From his fourth-down conversion attempts, to the uniforms OU wears, to McNeill’s role, there are no shortages of storylines as Riley enters his first season as the Sooner coach.

Riley’s biggest test will be handling himself if his coaching is cast in a negative light, as would be the case if OU lost to Ohio State and Texas by mid-October. He has recruited well, established rapport with media and properly represented the program. What he hasn’t done is won and lost.

If things turn upside down he’ll have his first true pressure test, and it’s difficult to envision a flustered Riley. His neutral personality has been a strength to this point. Senior linebacker Obo Okoronkwo even suggested recently that Riley is exhibiting a “swagger.”

• Watch this: This isn’t just Riley’s first season, it’s also OU’s first in 18 years without Bob Stoops on the sideline. A serious question: just where will Stoops situate himself on game days? He may not even know at this point.

This Week's Circulars