ENGLEWOOD, Colo. (AP) Trevor Siemian couldn't be rattled.
Not by the knee injury that ended his college career at Northwestern and scared away everyone but the Denver Broncos, who made him the 250th overall pick in last year's draft.
Not by his six-month audition for the Broncos' starting QB job that began with him as the dark horse against veteran Mark Sanchez and first-round draft pick Paxton Lynch.
He wasn't even unnerved Monday when coach Gary Kubiak informed him he'd won the job - making him the only QB with no passing attempts to take over a defending Super Bowl champion in Week 1.
''I feel like it's the right decision,'' said Kubiak, whose team opens against Carolina on Sept. 8 in a title game rematch. ''I believe in this kid and what he can do for our football team.''
Siemian was just as calm after the announcement as he's been every other day during his remarkable rise from part-time college starter to Peyton Manning's surprise successor.
''I'm not trying to be Peyton. I could probably get in a lot of trouble trying to be a first ballot Hall of Famer,'' Siemian said. ''So, those shoes are way too big to fill. I'm just trying to be the best man I can be every day, be the best teammate and take it from there.''
He has no plans to hit up Manning's phone, either.
''No, I'm sure he's pretty busy,'' Siemian said. ''He's probably got some commercials to shoot or something.''
Siemian says he pays no mind to the stress of the job. And he has no designs on changing his understated style, no plans to switch from the quiet, leader-by-example type to one who's more vocal.
''I don't think I want to change who I am or who I am in the locker room. I think we're really fortunate here we've got a lot of great leadership here in the locker room,'' Siemian said.
Siemian realizes a lot of NFL fans are asking who he is.
''That's a tough question,'' Siemian said. ''I like playing football. I try to be a good teammate, work every day, put my head down and be the best guy I can be.''
Siemian learned Kubiak's West Coast offense last year when he had a birds-eye view of the Broncos' QB conundrum that required the coach to gather his team every Monday from mid-November on to inform the players whether Manning or Brock Osweiler would start.
Kubiak said he won't pare the playbook for Siemian despite his inexperience - his only NFL snap was a kneel-down last year.
''If there's one thing that is a big strength of Trevor's is how much he can handle,'' Kubiak said.
Two things that impressed receiver Emmanuel Sanders about Siemian was his slow heartbeat and his lightning bolt of a right arm.
''He's very poised, even when he comes into the huddle, he's always the same guy,'' Sanders said. ''I remember when he first came in, I said, `You remind me a lot of Aaron Rodgers' in the way that he goes about his business and is always having fun, and even in the way he slings the football around. He's kind of that backyard football kind of guy. But yet he's still loose.
''I know everyone in the huddle enjoys when he comes in there because he's always cool, calm and collected.''
Siemian was an afterthought even after Manning's retirement and Osweiler departed in free agency. GM John Elway traded for Sanchez and tried to woo Colin Kaepernick, a quest he abandoned after drafting Lynch.
Meanwhile, Siemian was out to prove Elway had his man in Denver all along.
''Last year I got a chance to learn a lot and I was starting to get comfortable in the system, but I hadn't taken a lot of reps,'' Siemian said. ''So, coming back I got a chance to do that in OTAs and I think that's when I got a chance to grow a little more and pick things up and get comfortable with the guys and the scheme.''
Also invaluable to his development was running the scout team last year against Denver's dizzying defense.
''Yeah, it was an unbelievable challenge,'' Siemian said. ''You're forced to use your imagination a little bit against our guys, and you're right, I think going against them every day and getting your butt kicked a lot helped.''
Kubiak said Lynch will play the entire preseason finale at Arizona on Thursday night. He didn't say if Sanchez has a future in Denver. The Broncos would save $3.5 million and a conditional seventh-round draft pick if they cut him.
Sanchez hurt his chances with two red-zone fumbles against San Francisco, but Kubiak said it was more of what Siemian did that won him the job.
''He's earned the right to be our guy,'' Kubiak said. ''Is it a lot to ask of a young kid? Yes, it is. But it's not a lot to ask of our team. And I believe in our team. It's going to be about how we play as a group, not about one guy.''
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