As Oregon conducted its annual spring scrimmage at Autzen Stadium on Saturday, a strange occurrence related to the program happened in Chicago. In seven rounds and 253 picks of the NFL draft, zero former Ducks offensive players heard their name called.

For one of the premiere offenses in college football on an annual basis, it's a rarity: Only once since 1994 had Oregon gone an entire draft without an offensive player being picked. Oddly enough, that came in the 2011 draft, a few months after Oregon lost the BCS national title game to Auburn.

That Oregon's offense (from the defense, end DeForest Buckner and linebacker Joe Walker were picked) came up empty wasn't a big surprise, nor is an indictment of where the offense currently stands. Still, it reinforced the tight-rope walk that Oregon is navigating in its post-Marcus Mariota world, coming off a 9-4 season -- nothing to panic about, but the team's worst record since 2007 -- with competition in the Pac-12 North Division getting steeper.

The Ducks had pulled off a rare feat, emerging as a new national power with seven straight top-11 AP finishes. But now a season removed from the loss of a Heisman Trophy winner, it's getting more difficult to maintain a firm grip on that powerhouse status. While the defense was the real problem last season, it wasn't hard to spot cracks in the offense, despite its overall impressive production. When the entire identity of the program's rise is wrapped up in appearing to be invincible on offense, it's hard not to take note.

For Oregon, the monumental task of replacing Mariota in 2015 resulted in a creative and unusual move. The Ducks secured a commitment from graduate transfer Vernon Adams, a decorated FCS star who decided to spend his final season moving up a level to play against better competition, after being overlooked as a recruit.

Adams didn't arrive until mid-August, after fall camp had begun, but he still beat out veteran backup Jeff Lockie for the job. Early injury problems for Adams limited the potential of the offense, with the team teetering on disaster after a 3-3 start that included a 62-20 loss to Utah and the first Oregon loss at home to Washington State since 2003. Once Adams got healthy, the Oregon offense took off and looked like what we expect. The Ducks rattled off six wins in a row, scoring at least 38 points each time and overcoming a beatable defense to secure a bid to the Alamo Bowl … where more disaster struck.

After going ahead 31-0 in the first half, Oregon fell apart when Adams and center Matt Hegarty were sidelined with injuries. Despite the enormous halftime advantage, and despite the suspension of TCU star QB Trevone Boykin, the Ducks blew the entire lead and lost 47-41 in triple overtime, taking one of the worst losses imaginable into the offseason.

Adams was only a one-year answer, and despite recruiting a four-star quarterback in three of the last four classes, coach Mark Helfrich decided to look for outside help in a similar manner to last season, winning the sweepstakes for Montana State graduate transfer Dakota Prukop. Even if it was against Big Sky Conference competition, Prukop did exactly what you'd expect from an Oregon quarterback: He threw for 3,025 yards and 28 touchdowns, and he ran for 797 yards and 11 touchdowns. He's much more of a dual-threat quarterback than Adams -- who is quick and mobile but not a factor on designed runs -- and unlike his predecessor, he arrived at the start of the spring semester, meaning he has all offseason, instead of a couple weeks, to develop chemistry with teammates and try to secure the job.

Numerous names had a chance to provide competition, but as spring ball concludes, there is only one other name in the hunt competing with Prukop: Travis Jonsen, a four-star dual-threat recruit in the class of 2015, who redshirted in his first season on campus. Even though it was assumed that Prukop would follow Adams' lead and win the job with a lot of experience under his belt, there appears to be little separation after spring ball. Both produced mixed results in the spring scrimmage, which ended with a victory for Prukop's team after Jonsen's squad missed a two-point attempt for the win at the end of the game.

Prukop was efficient, completing 20 of 29 passes for 190 yards and two touchdowns while taking two sacks. Many of his completions were on short, quicker passes. Jonsen completed 15 of 24 passes for 188 yards with a passing TD, a rushing TD and a pick, and he also took six sacks. After two years in which the starting quarterback led the nation in passer rating -- Mariota in 2014, and Adams last season -- Oregon will likely take a leap back toward being more known for its explosive running game.

Whoever lines up at quarterback will be flanked by one of the deepest backfields in the nation, even after Thomas Tyner stepped away from the game. Royce Freeman doesn't get as much publicity, but he is in the same All-America conversation with fellow junior stars Leonard Fournette, Christian McCaffrey, Nick Chubb, Dalvin Cook and Samaje Perine. He's joined by a group of potentially exciting players, including Taj Griffin, Kani Benoit and Tony Brooks-James. The Ducks are also stronger at tight end, with Pharaoh Brown making a triumphant return from a horrible leg injury, and there is hope that the defense will take a step forward under new coordinator Brady Hoke -- who, despite his big problems as head coach at Michigan, fixed what was a broken Wolverines defense.

As usual, Oregon has lots of playmakers and lots of speed. As usual, it will be expected to be a Pac-12 frontrunner. However, the reasons to bet against the Ducks have grown. While the Pac-12 had a slightly disappointing 2015 season and didn't make the playoff, depth in the league is improving, particularly in the North. It's not just a coin flip between Stanford and Oregon for the division title, even though one or the other has won the division in each of its five years of existence since expansion. Washington is playing terrific defense and poised to take a leap forward on offense under Chris Petersen, with the Huskies a strong bet to get into the top 25 this fall. Washington State just went 9-4 and returns the league's best QB, Luke Falk, as Mike Leach's offense has finally found its groove. While destined to take a step back, even California just produced the No. 1 pick in the NFL draft. Only Oregon State truly lags behind.

Competition has increased, and Oregon doesn't hold the schematic advantage that it once did. Whereas its tempo took the college football world by storm under Chip Kelly, it's not something that defenses are unprepared for anymore. The Ducks are able to run tempo more effectively than most -- after all, they just finished fifth in yards per play -- but they ranked 22nd in plays per game last season at 76, with 11 teams breaking the 80 plays per game mark. Play-calling felt disjointed at times last season, and there aren't many surprises anymore as the rest of college football as followed the Ducks' lead.

Oregon is entering its second season without Mariota and fourth without Chip Kelly, and Helfrich will now move to his second offensive coordinator, with receivers coach Matt Lubick promoted to replace new UCF coach Scott Frost. Toss in the uncertainty at quarterback, including the lack of development of in-house QBs since Mariota, plus three new starters on the offensive line (the spring game featured 10 sacks total), and Oregon faces many more hurdles than it did just a couple years ago.

Despite the solid number of playmakers, the 2015 offense was wholly dependent on the health of Adams, the one-year Band-Aid, as we saw in the first half of the season and the Alamo Bowl. The end results still looked excellent statistically, but the offense had a surprisingly slight margin for error. While that could be expected after losing a Heisman winner, the fact that Oregon may go with another one-year FCS veteran fix at quarterback can't help buy raise eyebrows, even if the Adams experiment worked when he was 100 percent.

The Ducks remain in solid position entering the 2016 season. The defense should be better, and the offense is still capable of being explosive. But the departure of Mariota stripped the Ducks' offense of its feeling of invincibility -- and, thus, their identity -- and with the quarterback uncertainty lingering, that feeling of invincibility is only going to get harder and harder to win back, making this season a critical year to prevent the conference's balance of power from shifting too swiftly.

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Contact Matt at matt.brown5082@gmail.com and follow him on Twitter @MattBrownCFB and Facebook.

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