The day that Marcus Mariota envisioned as a fourth-grader is finally upon him Sunday.

He will play — and start — his first NFL game against Tampa Bay as the Tennessee Titans’ quarterback, fulfilling a vision he tightly held as a 9-year-old to someday, somewhere be a pro quarterback.

He wrote as much in a "What do you want to be when you grow up" assignment in Margie Tupper’s class at Nuuanu Elementary, while wearing a Dallas Cowboys’ jersey. It is a tale that has become the stuff of a TV commercial.

"I told him, there’s only so many quarterbacks in the NFL," Tupper recalls. " I told him, ‘Marcus, isn’t there something else that you’d also like to be?’ But he’d tell me, ‘No, Mrs. Tupper. That’s all I want to be.’ "

And despite the skepticism of some of his teachers and the long odds, he has not only reached the NFL but has become the face of the Titans franchise and the first rookie to start the season as quarterback in its half-century Houston-Tennessee history.

Now that it has arrived, the 2014 Heisman Trophy winner said it will come with a certain amount of butterflies. "I’ll get nerves, I get nerves before every game," Mariota acknowledged.

"My Dad, a long time ago, said, ‘If you do not have butterflies before each game, it means you don’t care enough,’ " Mariota said.

"It is just a matter of getting that first play out of the way and focusing now on what my job is. That’s kinda how it has always been."

Mariota said, "I don’t really focus on what’s going on in terms of my nerves, I just try to focus on what’s going on at the moment, that play and going from there."

Mariota recalled his first collegiate game as a redshirt freshman at Oregon. "It was my first live action and I didn’t know what to expect. I just remember getting hit against Arkansas State and realizing, ‘Yeah, you’re playing college football now.’ Dust yourself off and get ready for the next play.’

"I’m sure it will be something like that Sunday."

His task is to lead a resurgence for a downtrodden franchise that is coming off a 2-14 season, hence receiving the No. 2 pick in the 2015 NFL Draft, which it used to acquire him. And eventually move the Titans toward their first playoff berth in six years.

More immediately, Mariota says, "my job (is) to get those guys the ball and get the entire offense in the right position and the right situation. For me, I really think of myself as a distributor."

Titans linebacker Brian Orakpo said, "He’s ready to rock and roll, I really believe so. I don’t have any doubt in my mind that he’s not gonna take care of business. This guys is poised for this."

Tupper has said she rooted for Mariota. "But I felt kinda of silly having been the one who tried to talk him out of it at first. My son jokes with me about it, calling me ‘the dream killer.’"

But the dream and the passion behind it would not die.

Today is proof of that.

Reach Ferd Lewis at flewis@staradvertiser.com or 529-4820.