The declaration comes a day after the Steelers released their unofficial depth chart with Trubisky atop the quarterback pecking order.
"As you guys have seen because of the release of our depth chart, Mitch Trubisky is our starting quarterback and our captain," Tomlin told reporters. "Man, we're just really comfortable with what Mitch has shown us. He's a guy that came to us with franchise quarterback experience, if you will. He's comfortable in those shoes. He's been the focal point of a football team and an organization before, he's had success in doing so. Like I mentioned when we acquired him, he took the Bears to the playoffs two out of four years. He has a winning record as a starting quarterback. Those things were attractive to us. His athleticism and mobility were attractive to us. He took care of the football in-stadium. All of them did, and I think I'd be remiss if I didn't say that.
"It's good to come to decisions based on what people are doing as opposed to what people are not doing, and I thought all three of our quarterbacks represented themselves and us really well through this process. I thought they made plays. I thought they moved their units. I thought they took care of the football, so that made the decision-making a challenging one, but also a fun one as well. Mitch, as I mentioned, is really comfortable in those shoes and displayed that daily just about in any circumstance that you put him in."
Even with the Steelers selecting Kenny Pickett in the first round of this year's draft, Trubisky entered training camp as the leader for the starting gig. The 28-year-old did nothing to lose ground, even as the rookie shined. Trubisky played well during preseason action despite shaky play from his O-line.
Pickett improved during camp, pushing him to the No. 2 role ahead of Mason Rudolph, who Tomlin noted likely wouldn't be active Sunday.
"Really pleased with the growth and development of Kenny, that's why he's listed as No. 2," Tomlin said. "I thought his acceleration of development really took off once we stepped into stadiums. His decision-making, the fluidity of it, his competitive spirit, his pinpoint accuracy, all of those things I thought really came to the forefront once we started coming into stadiums, and I thought he grew and grew at a really fast pace once we got into stadiums. And I also think it's reasonable to expect that growth and development to continue as we push into the regular season.
"We're excited about where he is, and the ground that he's covered to this point, and the ground that he is going to continue to cover as we find our regular season rhythm and he gains an understanding of what that is, what preparation is like, what the rhythm of a seven-day process is like, in terms of getting ready for regular season ball and so forth. Just really excited about where he is and what he's capable of."
If Trubisky falters at all -- or goes down with injury -- the Pickett era will begin in earnest in Pittsburgh.
For now, it's Trubisky's chance to prove he can lead another team to the postseason, with a stiff test out of the gate against the reigning AFC champs.
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