There is no more dreaded phrase in the underclassman football lexicon than “sophomore slump.” It’s an all-encompassing term used to explain why a second-year player is struggling. Largely, it’s without base. Nobody really just slumps as a sophomore after a strong freshman year.

Usually, there’s a defined reason as to why a player isn’t performing up to expectations.

That’s what we’re looking at today. Several 2018 class stars, like Trevor Lawrence and Jaylen Waddle, aren’t producing at the level they were a season ago. They’re not alone. True Freshman All-American Caden Sterns and Adrian Martinez, a buzzy offseason Heisman dark horse, haven’t looked the same, either.

All four of those players were superstars after their first season on campus. To figure out what’s caused their slow starts, 247Sports consulted its deep stable of local experts.

Here’s what they had to say:

Trevor Lawrence, QB, Clemson | Justyn Ross, WR, Clemson

Lawrence and Ross were members of 247Sports True Freshman All-American team a season ago. But they didn’t truly experience a national breakout until the College Football Playoff, where the pair helped lead the Tigers to a national championship. Few players drew more hype than Lawrence and Ross this offseason – both fielded questions about potentially turning pro two years before they were eligible – and expectations were high.

That hasn’t really translated.

Lawrence hasn’t been bad by any measure. He ranks 14th nationally in QBR and leads the No. 2 team in the country. But his statistics are down in key categories (65.2 CMP% to 61.8%), and he’s already thrown more interceptions (5) than he did all of last season (4). Lawrence had Heisman-level expectations, and he hasn’t played to that level through five games.

Ross dazzled in the playoffs a season ago, catching a combined 12 passes for 301 yards and three touchdowns against Notre Dame and Alabama. Through four games this year, Ross has only caught 18 passes for 218 yards and a touchdown. He’s averaging just 12.1 yards a catch and sits well behind Tee Higgins’ pace (22 catches, 505 yards).

But context is important here. Lawrence hasn’t been amazing – he’s forcing some throws – but he’s still one of the nation’s best QB.

Ross, for his part, has battled a hamstring injury and also switched positions – from boundary to field receiver.

That’s why Clemson247’s Anna Hickey would tell people to calm down a bit.

“Too much was made out of Lawrence's five interceptions to start the season,” Hickey said. “Where the mark has been missed is Lawrence's inconsistency on throws that he made with ease last year, especially in the latter half of the season. He threw multiple receivers high on Saturday, but he also had plenty of pressure in his face. Jay Bateman, UNC defensive coordinator, deserves plenty of credit for that and for disguising his looks. I think it's a much more nuanced issue than categorizing Lawrence and Ross in 'sophomore slumps,' and Saturday brought that to the surface. The offense had to rely heavily on the explosive play because overall efficiency -- at quarterback, receiver, play-calling, offensive line, and running back -- was down. Saturday wasn't the first sign on that either. The offense as a unit just isn't on the same page right now.

"I think it's also worth pointing out 247Sports' Charles Power Week 2 theory that lack of wide receiver diversity on the roster might be something to monitor."

To Hickey’s point, the Tigers managed just 331 yards last week against North Carolina. Ninety-seven of those came on passes to Higgins or Ross. Clemson did not score on a drive in which it did not complete a pass of 28 yards or more.

Jaylen Waddle, WR, Alabama

Quick, who finished with the second-most receiving yards at Alabama last season? For those who picked Henry Ruggs or DeVonta Smith, you’d be wrong! Also, what are you doing? We’re clearly talking about Waddle.

The Houston native broke out in a huge way as a true freshman, earning 45 catches for 848 yards and seven touchdowns on the way to True Freshman All-American honors. Waddle, one of the most dominant 7-on-7 players ever, saw his quickness in the open field translate immediately. In fact, he finished seventh among all SEC players in receiving yards.

That’s why, at least on first glance, Waddle’s ho-hum sophomore season is confusing. Waddle ranks fourth the team with 12 catches for 197 yards. He’s yet to catch a touchdown.

Turns out that’s what happens when you’re playing next to one of the best wide receiving trios ever.

“Alabama's No. 3 wide receiver just surpassed Julio Jones and Amari Cooper for receiving yards and touchdowns in a game, so that kind of speaks to the guys Waddle has in front of him,” BamaOnLine Senior Analyst Travis Reier said. “Really, it was an injury to Smith last year that opened the door for Waddle. He took advantage of it and really came on over the second half of the season. Nothing has changed as far as what Waddle brings to the table; it's just crowded right now with a lot of guys looking to eat.”

For fans of Waddle, don’t worry. He’ll be a 1,000-yard receiver in 2020 when the trio in front of him starts playing on Sundays.

Caden Sterns, S, Texas

Sterns was, perhaps, the best defensive freshman in college football a season ago. The five-star safety finished with 62 tackles and four interceptions. Expectations were high entering his sophomore season, which hasn’t really had a chance to get going after he suffered an ankle injury in fall camp.

The sophomore safety, who plays across from All-Big 12 selection Brandon Jones, struggled early in the year along with most of the Longhorn secondary. Sterns’ tackle numbers (29) look great, but that’s partially because people are getting to the second level against the Longhorns.

Sterns played much better against Oklahoma State, but … he suffered an injury that will keep him out for four weeks, according to Texas head coach Tom Herman.

“An ankle injury in the preseason seemed to impact Sterns more than what was probably portrayed publicly,” Horns247’s Senior Writer Jeff Howe said. “Whether that was the case or not, Sterns didn’t play to his 2018 form, especially in a loss to LSU where he was put in some tough spots from a coverage standpoint. The worst part about the start to Sterns’ season is he played much better in a win over Oklahoma State (12 tackles, one tackle for loss) and was starting to look like himself before suffering a knee injury late in the game that could keep him out for up to a month. When healthy, Sterns has proven himself as one of the best safeties in the country. But he hasn’t been the same since a knee injury in the first half of a Big 12 championship game loss to Oklahoma ended his outstanding true freshman campaign.”

Adrian Martinez, QB, Nebraska

Hype can be a crazy thing in college football. Martinez experienced a bit of that this offseason when oddsmakers slotted him third behind Lawrence and Tua Tagovailoa in preseason Heisman odds. Keep in mind, Nebraska went 4-8 last season.

Make no mistake, Martinez is excellent. He finished his freshman season with 2,617 yards passing, 17 touchdowns against seven interceptions and a 64.6 completion percentage. He also rushed for 629 yards and eight touchdowns. Martinez is still playing pretty well early in his sophomore season. But his effort against Ohio State (8-for-17, 47 yards, 3 INTs) is what’s going to stick with the casual fan for a while.

“This last week he was (actually struggling),” said Husker247’s senior writer Brian Christopherson. “We are seeing flashes of what was expected from Martinez — expectations that were in the clouds and hard for anyone to reach — but his play has been disjointed. Just like the offense as a whole. And he had maybe his toughest night when everyone was watching, with three interceptions in the first 23 minutes.

“He can still take over games. Still has amazing talent. But he needs to find that consistent rhythm again, be more of that scary running threat he shows in spurts. And his o-line and receivers need to rise up and help.”

For the year, Martinez has thrown for 1,099 yards, 7 TDs against 5 INTs with a 59.5 CMP%. He’s also run for 315 yards and three touchdowns.