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Had you seen this headline 12 months ago, you’d have thought it was from The Onion: “Denver Broncos pay Case Keenum $18 million per season to be their savior.”

This is what it looks like when a team has to replace a legendary quarterback without much of a backup plan (listen up, New York Giants). The Broncos had a glorious four years with Peyton Manning, then he retired after Super Bowl 50. They let Brock Osweiler leave in free agency, a blessing in disguise. And they’ve been searching for a quarterback ever since.

First-round pick Paxton Lynch has shown nothing. Trevor Siemian turned into a pumpkin last year, and he was traded this offseason. Next up, the Broncos hope Keenum isn’t a one-year wonder.

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There’s no reason to believe Keenum’s surprising 2017 performance with the Minnesota Vikings was a fluke. The Broncos wouldn’t have given him a two-year, $36 million deal if major flaws showed up on film. All of Keenum’s success was from a solid foundation. However, it’s a small sample for a quarterback who never had anything resembling that level of NFL success before last season.

Keenum, 2012-16 with Rams and Texans: 454 of 777, 5,224 yards, 24 TDs, 20 INTs, 78.4 passer rating

Keenum, 2017 with Vikings: 325 of 481, 3,547 yards, 22 TDs, 7 INTs, 98.3 passer rating

Nobody saw Keenum’s 2017 season coming, including the 32 teams who were lukewarm on him as a backup in free agency last year. Keenum was unsigned a couple weeks into free agency last year when he settled for a one-year, $2 million deal from the Vikings. Then, at age 29, he was suddenly one of the NFL’s best quarterbacks. That kind of breakout is not unprecedented. It’s just rare and invites skepticism.

Broncos general manager John Elway was willing to gamble, mostly because he had to gamble on someone. It’s not like Elway is on the hot seat or his legacy is on the line with the Keenum move. Let’s just say Elway’s football legacy will be fine either way. But for as good as he was early in his time as Broncos GM, he has had a lot of recent missteps. It seems like forever since he drafted an impact player at quarterback, running back, receiver or tight end (it was 2011 when he took tight end Julius Thomas, and seven years in the NFL is forever ago). It isn’t too memorable when a team misses on a running back or defensive tackle in the draft. But when an all-time great quarterback whiffs on some quarterback decisions, everyone notices.

The quarterback issue is a big deal in Denver because the Broncos have rarely been bad through the past few decades, and the bones of that Super Bowl 50 title team are still around. When a core of Von Miller, Chris Harris, Demaryius Thomas, Emmanuel Sanders and others goes 5-11, all eyes focus on the quarterback. And the new coach.

Vance Joseph was in the worst position among the first-year head coaches last season. Kyle Shanahan could start 0-9 with the San Francisco 49ers, and nobody thought to criticize him. Joseph went 5-11, after being given a bad quarterback situation, and many people in Denver wanted him fired. The Broncos considered it.

Joseph made his mistakes after a 3-1 start that nobody remembers. A 23-10 loss to a winless New York Giants team on “Sunday Night Football” in Week 6 was perhaps the worst performance by an NFL team all last season, and a sign of things to come. The quarterback carousel became a mess. The offensive issues got so far out of Joseph’s control that he fired offensive coordinator Mike McCoy in midseason.

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“Early on in the season, I didn’t do a good job of pushing our coaches to make the proper changes that I thought could have helped us,” Joseph said, according to the Broncos’ transcripts. “I allowed guys to coach — that was my goal — but I wasn’t very good at coaching the coaches. I’ll get better at that. That was one of my shortcomings.”

Joseph mishandled a few things, but he was a rookie head coach. Not everyone can be Sean McVay. Elway gave him a second year, though the short wait to announce it let everyone know how close Joseph was to being one-and-done. That probably increased the pressure on Joseph for Year 2.

“I think he’ll be a better coach just from what he experienced last year having gone through that,” Elway said at the scouting combine. “It’s like I said, it’s like drinking through a fire hose for him. A lot of times you don’t know what you’re getting into until you actually become the head coach. I think Vance is a great young coach with a lot of energy.”

Because the Broncos aren’t far removed from a Super Bowl championship and some of those core players remain, expectations are probably higher than they should be. It doesn’t help that the GM won’t concede a step back.

“Life is too short to rebuild in the NFL,” Elway said at the combine.

So that’s where the Broncos are. With championship goals, but an aging roster that doesn’t have a lot of sure-fire offensive stars. It’s guided by a coach who hung in the wind for a while after the season, unsure if he’d be fired after one season.

And they’re banking on an undrafted quarterback with one great NFL season — and now an $18 million a year contract — to restore the glory.

View photos Case Keenum signed a large two-year deal with the Denver Broncos this offseason. (AP) More

I’ve praised John Elway and been critical of him. He has struggled the past few years, and not just to find a quarterback. However, this Broncos offseason was really good. I loved just about every pick the Broncos made in the draft. Bradley Chubb could have gone first overall and nobody would have thought twice. Denver got him with the fifth pick. Courtland Sutton has No. 1 receiver upside out of the second round. I’m still not sure why Royce Freeman wasn’t considered among the top non-Saquon Barkley backs in the draft; Denver got him in the third round. I liked the picks of linebacker Josey Jewell, receiver DaeSean Hamilton and tight end Troy Fumagalli too. I graded Denver as having the NFL’s best draft this year, and it wasn’t a tough decision. The free-agent class is basically just quarterback Case Keenum, though defensive lineman Clinton McDonald, punter Marquette King and cornerback Tramaine Brock were fine low-cost additions and safety Su’a Cravens and tackle Jared Veldheer were worthwhile trade gambles. While I have the same skepticism plenty of others do about Keenum, he had a remarkable 2017 and there’s no tangible reason to believe he can’t repeat it. Trading Aqib Talib was a blow to the defense, but the Broncos did very well on the whole.

GRADE: A

The good news about the Broncos offense is it can’t get much worse. The Case Keenum addition is the obvious change. But there are others. The running game wasn’t bad last year, but perhaps Royce Freeman and a motivated Devontae Booker can do even better. Emmanuel Sanders was hurt practically all last season with an ankle injury. Demaryius Thomas will be better with a legitimate quarterback. At tight end, Jake Butt (who was coming off a torn ACL at Michigan and redshirted last year) and rookie Troy Fumagalli could boost a position that has provided almost nothing the past couple years. The offensive line should improve with left tackle Garett Bolles in his second year, guard Ron Leary healthy again, underrated center Matt Paradis back and new right tackle Jared Veldheer added to the mix. Veldheer, acquired in a trade with the Arizona Cardinals, struggled last season but has been a top tackle before, so there’s hope. Keenum should have some help.

The Broncos defense looked beatable last season. In 2015, the Broncos defense became legendary by carrying a bad offense to a Super Bowl title. In 2016, Denver allowed a ridiculous 69.7 passer rating. Last season, it took a healthy step back. Denver allowed a 91.9 passer rating, tied for 20th in the NFL. Football Outsiders ranked Denver’s defense 10th in its DVOA per-play metric, and 15th against the pass. John Elway pointed out through the offseason the Broncos were 22nd in points allowed. It wasn’t a bad defense. It just wasn’t what we expect from the Broncos, and if we’re being honest, they probably aren’t making the playoffs without a top-five defense this season. And the defense no longer has cornerback Aqib Talib, traded to the Los Angeles Rams after making four Pro Bowls in his four Broncos seasons.

The NFL is about more than just the quarterback. The 2015 Broncos are proof – they won a Super Bowl with Peyton Manning posting a 67.9 passer rating as a shell of himself. But it’s obviously the most important position, and Case Keenum should be fine. Keenum ranked No. 1 among all quarterbacks in Football Outsiders’ DVOA, and Pro Football Focus had him No. 9 in its grades. I’m not necessarily buying Keenum as a top-nine quarterback, and he’s definitely not No. 1, but if he’s in the top half of the NFL this season it’s a huge upgrade for the Broncos. And if Keenum can’t recapture last season’s magic, it’s only a two-year contract.

At Demaryius Thomas’ peak, he was one of the best receivers in the NFL. Of course, his peak coincided with Peyton Manning’s time in Denver. Thomas’ receptions, yards, yards per catch and touchdowns have taken a tumble in each of the past three years (if we’re being technical, his touchdowns held steady from a disappointing five in 2016 to a disappointing five in 2017). He posted a 111-1,619-11 gem in 2014, and 83-949-5 last season. How much of that dip is due to quarterback play? Or was his phenomenal 2012-14 a product of playing with Manning, before Manning cratered in 2015? Thomas will turn 31 on Christmas this year, and if he doesn’t rebound with Case Keenum it’s probably best to assume this is his new baseline.

From Yahoo’s Brad Evans: “Paxton Lynch, Montee Ball, Cody Latimer … when it comes to drafting offensive talent, Denver GM John Elway has struck out with the frequency of this writer’s ultra-hyped sleeper picks (Terrelle Pryor, never forget). Hey, I can admire his consistency. Determined to make up for prior missteps, the embattled drafter climbed back on the horse and invested in receivers Courtland Sutton and DaeSean Hamilton along with running back Royce Freeman. At first blush, all are tremendous selections, particularly the latter.

“The former Duck is about to take flight in the Mile High City. Different from the undersized, scat type backs Oregon produced in recent years, he’s big bodied (5-foot-11, 235 pounds), bruising between the tackles (3.39 YAC/att in ’17) and surprisingly fast (4.54 40-yard dash). His vision, patience, footwork and hands are also pluses. Over his decorated college career, he routinely ripped through arm tackles and shook defenders in the open field (No. 11 in elusive rating last fall).

“Freeman’s odometer reading is already high and that limits his longevity, but he’s the clear-cut favorite to eclipse 250 touches right away. Devontae Booker and De’Angelo Henderson are not the answer. Suffice it to say, he’s the franchise’s new C.J. Anderson, a rusher capable of finishing inside the position’s top 15 as a rookie. Keep in mind, Case Keenum is a massive upgrade at quarterback and the Broncos’ supposed rickety offensive line ranked No. 9 in run-blocking efficiency last year. Don’t underestimate the potential. Topping 1,300 combined yards with seven-plus scores is doable in Year 1. Continue to pull a fast one on your opponents at his 59.7 ADP (RB27).”

[Booms/Busts: Fantasy outlook on the Broncos.]

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The Broncos turned the ball over 34 times last season. Only the Cleveland Browns, who acted like giving the ball away was their job and did so 41 times, were worse. No other team had 30 giveaways. When you have as many defensive playmakers as Denver, your turnover margin should never be minus-17, second-worst in the NFL. Case Keenum was tied for fourth-best in the NFL last season with a 1.5 interception percentage, and that’s a welcomed sight in Denver.

DID YOU KNOW VON MILLER HAS NEVER WON DEFENSIVE PLAYER OF THE YEAR?

It’s a strange bit of trivia, like Kobe Bryant winning only one MVP or Drew Brees never winning an MVP. You assume Miller has a DPOY award, but no. A reasonable argument can be made that Miller is the most talented player to not win that award, though guys like Junior Seau and Ronnie Lott have a strong case for that title.

Nevertheless, you assume Miller will get one in his career. He has a Super Bowl MVP, after all, and has been one of the best players in the NFL for years. Don’t rule it out this year. Bradley Chubb, the fifth pick of the draft, should take some attention away. Two of Miller’s three All-Pro seasons came with DeMarcus Ware as a teammate, and perhaps Chubb could have a similar impact. Miller is 29 years old, still well within his prime, but he might want to hurry up if he wants to add that trophy to his case.

This is easy: Case Keenum plays like he did last season, the defense rebounds to 2015-16 levels and the Broncos win the AFC West with ease. It can be demoralizing for a team when it has a terrible quarterback situation, and the Broncos seemed beaten down by the end of last season. Keenum should bring a lot of tangible benefits to the offense, but he also provides hope to a locker room that needed it. The Broncos believed in Keenum all along, making him their target this offseason, and if Keenum is the answer then everyone will benefit.

There’s plenty of reason to question if the Vance Joseph-Case Keenum combination is the right one. Also, the proven impact players the Broncos have under 29 years old are defensive end Derek Wolfe and cornerback Bradley Roby … and that’s probably the extent of the list. This draft better be as good as it looks on paper. If Keenum struggles, the rest of the roster looks old and Denver has double-digit losses again, Joseph isn’t going to survive it. And then John Elway might have to finally admit he needs to rebuild.

You can talk yourself into the Broncos being very good this season. Still, there are too many questions to pencil them into the playoffs. Somewhere around .500 is probably the right answer, but that’s not a great look for an old roster that just invested in a 30-year-old quarterback. The pressure is high in Denver and 8-8 seems like failure, even though that’s a probable outcome.

32. Cleveland Browns

31. Indianapolis Colts

30. New York Jets

29. Arizona Cardinals

28. Buffalo Bills

27. Cincinnati Bengals

26. Chicago Bears

25. New York Giants

24. Miami Dolphins

23. Washington Redskins

22. Tampa Bay Buccaneers

21. Houston Texans

20. Seattle Seahawks

19. Oakland Raiders

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Frank Schwab is a writer for Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!

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