THE DIRECTIVE CAME from D'Anton Lynn, the man who might be most significant in shaping USC's trajectory this coming season.

Lynn's goal wasn't uncommon, especially for a coordinator taking over a struggling defense. Coaches often want players to transform their bodies. The first item in the offseason credo -- bigger, stronger, faster -- isn't just a buzzword.

But Lynn's desire for USC defenders to get bigger, especially along the line, carries more weight, quite literally, because the Trojans, along with UCLA, Oregon and Washington, are making the move from the Pac-12 to the Big Ten, a conference known for size and bruising line-of-scrimmage play.

Although the Big Ten isn't exactly what it was under Woody and Bo, the narrative remains. Michigan's national championship in January reinforced the reputation that physical line-of-scrimmage play wins, not only in the Big Ten but beyond.

The Pac-12 also carried a tag, often attached too liberally, that its teams lack the bulk and brawn to thrive up front. The four West Coast transplants enter the Big Ten with different types of players, levels of depth and schematic philosophies, but all face the stigma that they will struggle without adding mass.

"That's my philosophy, everywhere I've been," Lynn, who spent last season as UCLA's defensive coordinator after cutting his teeth in the NFL, told ESPN. "You want to be big and strong up front, you want to build the wall. Being in the Pac-12 last year was the most spread I've seen, as far as offenses. Going to the Big Ten will be more of what you see in the NFL. It's a more physical style of play. You get bigger personnel groups.

"Being able to win the line of scrimmage is going to be even more important."

Coaches for incumbent Big Ten teams view the West Coast newcomers with respect, and expect them to hold their own right away.

"They're not going to have a size issue," Purdue coach Ryan Walters said of the West Coast newcomers.

There are some nuances, though, between the conferences. When discussing the Pac-12 arrivals, several Big Ten coaches highlighted Michigan's 32 consecutive run plays to beat Penn State last year on the road.

"The physicality in this league is something that stands out to people from the outside world, when you come in," Illinois coach Bret Bielema said. "It's just a different game, out there [on the West Coast], than what the Big Ten does."

USC players have spent the past seven months packing on muscle mass. According to Rachel Suba, USC's director of sports nutrition, Trojans players added a total of more than 1,450 pounds this offseason. Players at Oregon, Washington and UCLA are also changing their bodies. But questions remain about whether the offseason bulk-up is standard, Big Ten-driven or even necessary.

How much bigger should the Pac-12 newcomers become to thrive in the Big Ten?

USC WENT THROUGH the 2023 season with a defensive line that prioritized quickness over power. The Trojans primarily started two ends, Solomon Byrd and Jamil Muhammad, who weighed 250 pounds, and had only one end in its rotation, Anthony Lucas, who topped 250. The line was a bit bigger inside, although Georgia transfer Bear Alexander (300) and Arizona transfer Kyon Barrs (275) were the only tackles heavier than 275 pounds.

Even the linebacker rotation featured leaner players, as only Mason Cobb and Shane Lee were listed at more than 230 pounds.

"You look at just the size of their butts and their legs and their shoulders, it's not big enough for a team that wants to win championships," said Geoff Schwartz, a former offensive lineman at Oregon and in the NFL, who works as an analyst for SiriusXM and Fox Sports. "So it's not just about taking the guy who's 6-2, 290 and making him now 6-2, 310. That's great. USC just needs bigger humans inside.

"Lincoln Riley understands that."

The Trojans tumbled to 118th nationally in points allowed (34.4 PPG) and 110th in yards per rush allowed (4.8). Nine teams rushed for 198 yards or more against USC, including Washington, which put up 316. The unit's problems went beyond one area, leading to the November firing of coordinator Alex Grinch, but size jumped out as an area to repair.

"[Getting bigger] just needed to happen, just trying to get us ready for all leagues and all opponents," Riley told ESPN. "Then, certainly from a scheme standpoint, with what we're doing, it needed to happen as well. It was something pretty clear that we were gonna go full speed with."

The shift in body composition for USC players went beyond simply gaining weight.

"We might want this position to weigh this much, but a guy might not be built to weigh that much," Lynn said. "What is the most that we can get on this guy's body to where it doesn't sacrifice the way that he moves?"

Lynn made a similar request in 2023 when he arrived at UCLA, but also inherited a Bruins defensive line that more closely resembled his vision. UCLA went on to finish second nationally in rushing defense, while producing the first defender taken in April's NFL draft, Laiatu Latu, and several solid performers (Gabriel Murphy, Grayson Murphy, Jay Toia).

USC had a greater need for bulk, and to Lynn, the Big Ten move accentuated that. Although the Big Ten has changed since Lynn played cornerback at Penn State from 2008 to 2011, the league still features personnel groupings -- one back and two or three tight ends, two backs and two tight ends -- that USC didn't see as often in the Pac-12.

"Overall, it's still a bigger conference," Lynn said. "You get big O-linemen, big tight ends. At the same time, a lot of those schools have the ability to get into smaller personnel groups, to spread the field out, and they have a lot of speed. You have to be able to stop everything."

USC's offensive line didn't have as much of a size deficiency, but offseason gains still were needed. Jonah Monheim, who started at right tackle in 2022 and left tackle in 2023, has always been tagged as a "weight-gain guy," and played last season at around 295 pounds. After consulting with director of sports performance Bennie Wylie and the coaches, Monheim added about 15 pounds during the offseason, and will play center this fall.

"I've always played lighter and pretty underweight for an offensive lineman," Monheim said. "[The gains] are something that would have needed to happen, regardless of conference, as an individual, and it just gets amplified with the conference change."

Bigger offensive linemen also made modest gains, like Emmanuel Pregnon (315 pounds to 320) and Mason Murphy (310 to 315). Riley said the overall weight gains are ahead of where he expected entering camp, which began this week.

"You'll learn more about it actually late in the season, as you get into some of those big games," Riley said. "When some guys are banged up or you're playing with your second-string left guard or your third-string defensive end, how are you still able to be effective against a really good team?"

How USC holds up along both lines will be closely watched in Year 1 of its Big Ten voyage. But what about the other Big Ten newcomers?

OF THE FOUR West Coast teams entering the Big Ten, USC had the largest bulk gaps to fill. Oregon and Washington are on the other end of the size spectrum.

The Ducks became a line-of-scrimmage-based program well before the Big Ten move. Former coach Mario Cristobal, one of the nation's top recruiters and offensive line coaches, molded the Ducks' offensive front into one of the nation's best before going to Miami. Dan Lanning replaced Cristobal after the 2021 season and has continued to emphasize line play, both in development and through recruiting and transfer portal additions.

Oregon has had nine offensive or defensive linemen selected in the past five drafts, including first-round draft picks Kayvon Thibodeaux and Penei Sewell. The team returns accomplished linemen such as tackle Josh Conerly Jr. and Ajani Cornelius on offense, and Jordan Burch on defense.

"Oregon's built well up front ...," said CBS analyst Aaron Taylor, an All-America tackle at Notre Dame who played in the NFL and founded the Joe Moore Award, given to the nation's top collegiate offensive line unit. "They can compete for [the Big Ten] title and compete for a national title this year on the lines of scrimmage."

Schwartz agrees that of the four Big Ten newcomers, Oregon is set up best for the transition with its line play. Lanning has told Schwartz that he wants robust rotations up front. Defensive linemen, for example, should play a maximum of 40 snaps, which is what Lanning targeted as Georgia's defensive coordinator when the Bulldogs won the national title in 2021.

Lanning also wants a team built to last in a taxing conference. Three of his five losses as Ducks coach have occurred on Nov. 12 or later.

"We always want to be bigger," Lanning told ESPN. "It wasn't like we had to change what we're doing, because at the end of the day, that's the same thing that would have won us games in the league we were just in."

Oregon might have the most Big Ten-ready roster of the West Coast arrivals, but Washington boasted the most decorated line in 2023. The Huskies captured the Joe Moore Award, ending Michigan's two-year run with the sport's largest trophy. Although Washington operated a pass-heavy offense, it finished third nationally in percentage of sacks allowed per dropback (3.4%), despite ranking fourth in total dropbacks (594).

But the Huskies looked flustered at times in the national title game against Michigan, which held Washington to 46 rushing yards and twice intercepted quarterback Michael Penix Jr.

"A tougher, more physical defensive unit was able to get after them," Taylor said. "Lines of scrimmage are always where this game is won and lost. You can throw the ball around the yard all you want, but can you get first downs? Can you get stops? Can you get touchdowns in the red zone? You need big, burly dudes up front to be able to do that."

The Huskies lose all five line starters, part of a total roster reboot under first-year coach Jedd Fisch. Washington will go with a transfer-heavy group that includes San Diego State's Drew Azzopardi (6-7, 308), Ohio State's Enokk Vimahi (6-4, 301), as well as holdovers Landen Hatchett (6-2, 310) and Gaard Memmelaar (6-4, 299). The defensive line must replace first-team All-Pac-12 end Bralen Trice, as well as multiyear starters Zion Tupuola-Fetui and Tuli Letuligasenoa.

Fisch knows the Big Ten from previous assistant stops at Michigan (2015-16) and Minnesota (2009). As Arizona's coach, he upgraded the team's lines, which featured 2024 first-round NFL draft pick Jordan Morgan and Jonah Savaiinaea, a potential high draft pick in 2025.

"We want a Big Ten offensive line, we want a Big Ten defensive line, and that's what we built in Arizona," Fisch told ESPN. "I don't believe in undersized guys. We try to build our team to look like an NFL team, so the Big Ten is a good place to do that."

Fisch displays pictures of NFL players out of uniform throughout Washington's facility, to help his players visualize how their bodies must evolve. He has already seen gains from linemen such as Max McCree (28 pounds) and Paki Finau (24 pounds).

"It's huge for our guys to understand how important it is to get big at every position," Fisch said.

UCLA also has a new coach in DeShaun Foster, but there is less roster turbulence, in part because Foster, a Bruins assistant for the past seven seasons, limited portal departures during the transition. Although the defensive line will have a largely new look, UCLA retained Toia, who briefly entered the portal and projects as one of the Big Ten's top interior linemen at 6-foot-3 and 325 pounds.

The Bruins also bring back starting offensive linemen Spencer Holstege (6-5, 310), Josh Carlin (6-5, 310) and Garrett DiGiorgio (6-6, 310) from a group that led the Pac-12 and rank 16th nationally in rushing average (197.9 ypg). Foster told ESPN he sought bigger bodies from the portal, adding Houston and Louisville's Reuben Unije (6-5, 310) and UNLV's Alani Makihele (6-5, 350).

Toia actually tried to cut some weight, 10-15 pounds, to improve his quickness.

"We're going into a different conference, a more physical conference, from what [the coaches] have described," he said. "The Big Ten is known for its O-linemen. You look at Nebraska, Iowa, Ohio State, everybody. It's just a better opportunity for me to go out there and compete."

PLAYERS FROM UCLA, Washington, Oregon and USC are aware of the labels placed on their former league, and their new one.

"Everyone looks at the West Coast, the Pac-12, and it is fast, it's electric football and it's high scoring," Oregon tight end Terrance Ferguson said. "But we run the ball well and we take pride in our trenches."

Added Washington safety Kamren Fabiculanan: "The West Coast, I guess, has a reputation with the East Coast saying that we're small and we're not ready for the [Big Ten]. But football is football."

The league reputations may be real, but how close are they to reality? The Pac-12 delivered its best season of the CFP era in 2023, led by arguably the best quarterback class for any league in recent history. The league finished with one more NFL draft pick (43) than the Big Ten (42), which was boosted by a team-record 13 from Michigan. The Big Ten had 10 offensive linemen selected, three more than the Pac-12, which had more first-round selections (3-1). Both leagues produced six defensive linemen, while the Big Ten had four linebackers drafted, one more than the Pac-12.

Of the seven semifinalists for the Outland Trophy, given to the nation's top interior lineman, the Pac-12 and Big Ten each had two representatives. Latu won the Rotary Lombardi Award as the nation's top lineman, while Utah's Jonah Elliss was also one of four finalists.

USC, Washington and Oregon all had quarterbacks selected in the top 12 picks of the NFL draft, and all are expected to remain top passing offenses. The Big Ten also has to adjust to what its new league members can do.

"The biggest adjustments are going to be some of the old school Big Ten mentality of, 'Stop the run, stop the run, stop the run,'" Northwestern coach David Braun said. "You go into that mentality against USC, Lincoln and those guys are going to throw the ball for 500 yards on you."

Penn State coach James Franklin thinks the perception differences between the leagues are overstated.

"If this would have been the '70s or the '80s, when the Big Ten was such a heavy-run conference and the Pac-12 was very pass heavy, then yes," Franklin said. "That stigma is still with the Big Ten, but that's not even really who we are anymore."

USC is still going to operate the dynamic offense that propelled Riley's career. But to reach the CFP for the first time, especially in the Big Ten, the Trojans need balance and brawn, and they're rounding into form.

"When people watch us on tape, we want our physicality to stick out," Lynn said. "Being able to win the line of scrimmage is going to be even more important, because there's more teams in that conference that are going to test you up front."