College football season is over four months away and many teams are in the midst of preparations. One of those is USC football, which didn't have the most ideal campaign last year. The Trojans finished the 2023 regular season with a 7-5 record, taking a step back from their highly competitive run the year prior. Head coach Lincoln Riley knows which parts of the roster need tweaking. Joining 247 Sports' Brandon Marcello for a discussion, Riley revealed what he thinks is USC's biggest need heading into the upcoming season.

“…Probably an interior defensive lineman, that's probably the biggest need,” Riley said, per 247 Sports' official X (Twitter) account.

Last year, USC allowed 246.4 opponent passing yards per game, finishing 103rd among all FBS schools. While this could be due to many factors, such as playing in a highly talented Pac-12 conference, the lack of D-Line impact is possibly a big part of the equation.

The Trojans' need for a defensive tackle is just the forefront of an overall defensive issue. USC may have had a Caleb Williams-led offense last year, but they faced struggles on the other side of the ball. The team gave up a total of 34.4 opponent points per game — 121st out of all FBS schools. In addition, USC's opponent-rushing-yard ranking is also outside the top 100.

Lincoln Riley and USC football prepare for the 2024 season

USC Trojans quarterback Caleb Williams (13) talks with USC Trojans head coach Lincoln Riley during the first half of the game against No. 6 Oregon Ducks on Saturday, Nov. 11, 2023, at Autzen Stadium in Eugene, Ore
Abigail Dollins / USA TODAY NETWORK

Nevertheless, there are plenty of shakeups within USC's roster. The Trojans have been very active with recruits and incoming transfers, which is presumably why Riley likes what he currently sees from the team.

“…We'll look at a couple of other guys as this thing evolves but we really like the group we have out there. There's a lot of continuity, there's a lot of competition across the board,” he added.

As of now, USC has 10 incoming transferees, headlined by former UNLV quarterback Jayden Maiava. While the team did lose the commitment of DL Isaiah Raikes, there are still new defensive faces for the upcoming season. USC football will be welcoming players such as Nate Clifton (DL), Easton Mascarenas-Arnold (linebacker), Akili Arnold (safety), John Humphrey (CB) and DeCarlos Nicholson (CB).

Clifton led Vanderbilt in sacks last season. Easton Mascarenas-Arnold was arguably Oregon State's top defensive player while his brother Akili was also a key piece for the Beavers. Humphrey and Nicholson made valuable contributions to UCLA and Mississippi State, respectively.

Although USC does have more than 20 players who are headed to the transfer portal, Riley would rather put his focus on those who chose to remain.

“I've said the same thing to USC fans, USC people, but really across college football — Keep the focus on the other hundred guys that are staying in your program, that are loyal to your program, that are not even thinking not one bit about going to the transfer portal.”

As season three with USC football awaits Lincoln Riley, he and the team are surely eager to make noise as newcomers in the Big 10.