Ollie Jung | Daily TrojanThis isn’t exactly what we expected.UCLA will make the trip to South Central on Saturday to take on the Trojans in a primetime matchup. This was a game all fans had circled on their calendars when schedules were first released last year: It would be a showdown between the nation’s two premier quarterbacks — redshirt sophomore Sam Darnold and junior Josh Rosen — as they duked it out to be the No. 1 overall pick in next year’s NFL Draft, and whether it was for one team or both, there would likely be significant postseason implications on the line.After three months of up-and-down college football in Los Angeles, much has changed. Darnold has taken a step back somewhat after his blistering debut campaign, struggling with turnovers and sparking rumors he may return to school next fall. Meanwhile, Rosen has spearheaded a powerful UCLA passing attack, but has also thrown nine interceptions (Darnold has 11) while steering his team to a 5-5 overall record. Forget playoffs: The Bruins are fighting for bowl eligibility, and on the other side, No. 11 USC, despite clinching the Pac-12 South in Colorado last Saturday, blew its national championship hopes weeks ago. The stakes might not be the same as they were expected to be at the beginning of the season, but they still remain high and serious for both teams.So if this weekend’s game is neither a playoff chase nor a de facto battle for the top draft pick, then what are we looking forward to? Pride aside, does it even matter whether the Trojans win or lose in the rivalry face-off at the Coliseum on Saturday? In another year, the answer to that question would actually be a clear no. With a Pac-12 Championship berth already secured, USC could take it half-speed against the Bruins and essentially give itself two weeks off before fighting for the conference crown on Dec. 1. Then, with a win in Santa Clara, it would be on to the Rose Bowl.But no roses await the Trojans this year, as Pasadena hosts a leg of the playoff. With a run at the national title out of reach (barring one of the most absurd final three weeks in college football history), USC can only hope for the best possible at-large bowl bid, meaning a loss to UCLA could prove catastrophic. In the past, the Rose Bowl provided a sense of security for the Trojans as long as they won the conference. This year, it’s all different.A random bowl berth may sound trivial — it probably is in reality — but for the Trojans this season, perception has been everything. A trip to Glendale for the Fiesta Bowl looks a whole lot better than a trip to San Diego for another Holiday Bowl, and that could make all the difference for this team.Think about it: Imagine if USC takes down UCLA on Saturday before winning the Pac-12 two weeks later. If the Trojans beat a team like, say, No. 6 Auburn in the Fiesta Bowl (or even played a competitive game), the season could be considered a success. Sure, there will always be the disappointment of falling short of a national title, but wrapping up the campaign as a two- or three-loss conference champion in a New Year’s Six bowl would be a worthy follow up to last season’s Rose Bowl victory, and it would show that this team is consistently remaining in the top tier of national competition.On the other hand, if the Trojans fall to the Bruins this week, not only would they suffer their second rivalry loss of the season, but they would also play themselves out of a marquee bowl — even with a conference championship. Despite the team’s late-season surge, question marks remain about USC’s consistency on either side of the ball, and the full-blown panic that set in after the humiliation at Notre Dame last month would return if the Trojans can’t put away a middling UCLA squad at home. This is a must-win game in the sense that the win is completely expected; if the Trojans can’t perform, their skill will be called into question, especially after they didn’t move up at all in the CFP ranking despite a win last week.In fact, a loss to the Bruins resigns USC to at least a three-loss season, and with a complete loss of momentum, you’d anticipate more to follow: The campaign would end no differently than it did under the likes of former quarterback Cody Kessler or former coaches Ed Orgeron and Steve Sarkisian. The pressure is now heavy on Darnold and head coach Clay Helton to prove that the program has advanced beyond those days.Of course, crushing the Bruins won’t mean anything without a win two weeks later, as a loss in the Pac-12 Championship would condemn the Trojans to the same fate as a loss to UCLA would. But that’s a problem for later, and the Trojans will be best to focus on the game at hand, especially since they won’t know their opponent for the conference championship until next week. The season is on the line this Saturday. Darnold has the opportunity to boost himself to 2-0 in his career against UCLA and lift USC to another double-digit-win campaign — with two more on the horizon. Meanwhile, Rosen and the Bruins are fighting to earn bowl eligibility and keep their year alive, and they have a chance to throw a wrench into the Trojans’ season en route to some sort of redemption in a bowl game.It’s all to play for this weekend, and we get to see two of the top quarterbacks in the country go head-to-head to keep their campaigns alive. It’s not the Pac-12 South title showdown we saw in 2015, but each team desperately needs a win. It’s also the first (and possibly only) edition of Darnold vs. Rosen. What more can you ask for?Oliver Jung is a senior majoring in print and digital journalism. He is also the sports editor of the Daily Trojan. His column, “Jung Money,” runs Fridays.