USC has its second and perhaps most important preseason scrimmage Saturday afternoon as the Trojans will play in the Coliseum in front of fans as part of the program's Fall Showcase.

While head coach Clay Helton has asserted that the depth chart won't be set until the Friday before the Aug. 31 season opener against Fresno State, it's more likely that some key decisions will be made after this scrimmage as the Trojans head into game prep starting Monday.

Offensive coordinator Graham Harrell has suggested he wanted to pare down the quarterback competition and redistribute reps to the top one or two QBs after a week and a half or so of camp, which has already passed. And defensive backs coach Greg Burns said he'd be making final decisions on his starters in the secondary following this scrimmage.

So whether a formal depth chart is publicly released next week or not, this is a pivotal showcase for everybody involved.

Here are five storylines of particular interest today.

It was even earlier last August that JT Daniels, then a true freshmen with barely two weeks of college practices, effectively seized full control of the Trojans quarterback competition during a scrimmage in the Coliseum.

A formal announcement wouldn't come until much later, but after he clearly outpaced his challengers that day any doubt was removed as to his standing on the depth chart.

More than a year later, USC is still dividing reps pretty evenly between four quarterbacks. Daniels remains the presumed favorite to start, and Helton said Thursday that the sophomore has "been really consistent through" camp.

Daniels has been steady if unspectacular, but none of the Trojans' other QBs have truly made a case to usurp him. Freshman Kedon Slovis started the month very strong, but he struggled in the first scrimmage with a couple interceptions and had an uneven week thereafter. Jack Sears, the only other QB on the roster to start a game, has had some nice moments but not enough to change perceptions. And Matt Fink projects as veteran depth.

Perhaps a strong performance Saturday by Daniels -- one somewhat reminiscent of his first Coliseum scrimmage last year -- could help expedite a decision and redistribution of reps in practice.

The last pass he threw was a pick-6 to safety Talanoa Hufanga at the end of practice Thursday, so it will be interesting in general to see how he responds and performs in this one.

USC defensive backs coach Greg Burns said he was still evaluating two to three spots in his secondary and wanted to use the rest of this week to reach his decisions.

The competition at cornerback, where the Trojans have such minimal returning experience, has been the most intriguing battle of camp.

Sophomore Olaijah Griffin has been the most impressive of the corners and would seem likely to secure one of the two starting jobs. He simply has the most upside of anyone in the mix.

The other spot is tougher to call. Redshirt sophomore Greg Johnson is the only USC corner with any meaningful experience, but he struggled last fall in those opportunities and has not overwhelmed in camp.

Defensive coordinator Clancy Pendergast this week highlighted Griffin, redshirt freshman Isaac Taylor-Stuart and freshman Chris Steele as making "jumps" this preseason. That could be read as Johnson being a notable omission from that praise or not qualifying as he has more experience than the others. Johnson has also been cross training a good bit at nickel, so that he might be ready if needed there during the season, and that could reflect the coaches' comfort level with what they've seen from him at corner already.

It's hard to say. Steele, the 5-star freshman transfer from Florida, has drawn repeated praise from Helton and Pendergast. He has obvious upside and plays with confidence, but he has already developed a reputation and penchant for racking up penalties. And Taylor-Stuart, another 5-star prospect, continues to progress in his second year in the program, but he has always been viewed as more raw than the other corners and it remains to be seen how much the coaches' trust in him has truly grown.

A big day Saturday by any of those contenders could be impactful, but don't read too much into who lines up with the first team or second team. Burns has been rotating them strategically and that is expected to continue through this scrimmage.

Redshirt junior Velus Jones was one of the stars of USC's first scrimmage, hauling in two deep touchdown receptions (albeit both against freshman corner Adonis Otey).

He's had a great camp in general and an especially good last week, parlaying his speed into big plays both downfield and on catch-and-runs across the middle. He would seem to have earned a decent role in the offense and could be in line for a long-awaited breakout season.

"I think we use him in a lot of things, especially when you're fast," Harrell said this week. "Obviously he's caught some deep balls because of his speed, but he's the kind of guy that if you can get the ball in his hands he has the chance to be pretty special with it because he has a gear that most people don't have."

But it wouldn't hurt to keep reinforcing that for the coaching staff. Harrell also noted that it would have been nice to see Jones go through spring practice. He didn't return from the NCAA transfer portal until this summer, so he's still making a first impression on his new OC.

It remains anybody's guess how snaps will be divided between the running backs this season. Harrell noted that with USC's limited full-padded practices, the running game often hasn't been a full reflection of what it could be.

But nonetheless, redshirt freshman Markese Stepp has been consistently impressive. The 235-pound bruiser has looked much more comfortable catching passes out of the backfield -- something he needed to show to help his bid for playing time -- and he's made it clear that he will be tough to bring down when given the chance to carry the ball.

USC doesn't have another back like him, and with none of the other rushers especially standing out Stepp has certainly helped his standing this month.

A big performance in the Coliseum on Saturday would further boost his cause, though.

Helton and Harrell have both been pleased with the offensive line this month, but it's often tough to get a true read on line play during camp.

How does one know which side is truly performing well independent of the other?

Well, there is considerable expectation for USC's defensive line with freshman Drake Jackson showing true breakout potential, fellow DE Christian Rector looking to put it all together as a redshirt senior, redshirt sophomore DT Jay Tufele a bankable producer and redshirt sophomore DT Marlon Tuipulotu an underrated asset in the middle.

The USC offensive line, meanwhile, will continue to have much to prove heading into the season.

But getting another extended glimpse at those units competing head to head in a scrimmage setting Saturday will provide another gauge from which to base expectations.

1 p.m. – Parking lots open

1:30 p.m. – Gate 1 (Peristyle) opens to the public for assembly for player autograph session

1:30 p.m. to 3 p.m. – Traveler at Gate 1 (Peristyle)

2 p.m. – USC team arrives (Peristyle)

2:15 p.m. to 3:15 p.m. – Player autographs (Peristyle)

2:30 p.m. – Gates 4 and 7 (south side) open to the public for scrimmage and tour entry

2:30 p.m. to 6 p.m. – Concessions open (Heritage Concourse)

4 p.m. – On-field recognition of USC anniversary teams (1969, 1994, 2009)

4:15 p.m. – Team warm-up

4:30 p.m. to 6:30 p.m. – Scrimmage

**Event tickets are complimentary to season ticket holders (1 per season ticket), students with ID and children under 2; others can purchase tickets the day of the event ($15) at the Gate 1 ticket office. All seating is on the south side and is unreserved. Those who have season tickets on the north side can visit their seats from 5:30 p.m. to 6:30 p.m.

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