Mason Fine had one job as he watched the most exciting play of the college football season unfold.

As Keegan Brewer raced 90 yards with a surreptitious punt return that set the tone in North Texas’ 44-17 victory at Arkansas, the Mean Green quarterback was charged with “making sure no one steps foot on the field.”

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Fine admittedly wasn’t sold his team's trick play would work. Brewer was told to catch the punt and stand there as if he'd called a fair catch, hoping no one would hit him. If he sold it well enough, his teammates and coaches would complete the deception — and ensure the Mean Green wouldn't be called for too many men on the field. All of it was to make sure no one in Razorback Stadium caught on to the chicanery.

“I remember when it was happening, I had to catch myself from running on the football field — and I knew it was coming,” Fine told Sporting News. “I didn’t think it was going to work, to be honest with you. I was like, ‘Man, you’re going to get my guy Keegan killed!’ I was watching it and I was like ‘Holy crap, they’re not tackling him; this might actually work.’ And then he just started running.”

It was the play that stands out most in North Texas’ seemingly unlikely victory against the Razorbacks, yet it was merely one snap on a day that was decisively ruled — offensively, defensively, on special teams, in the trenches, down the field, on the sidelines — by the Mean Green.

“Went out there and really dominated on all three sides of the ball,” UNT coach Seth Littrell said this week during his news conference. “That’s a credit to those guys, their preparation and what they continue to do every week.”

It’s also a credit to Littrell for changing the culture in Denton, Texas — something he knew a little about before becoming the Mean Green's coach. The former Oklahoma fullback helped helped Bob Stoops transform Oklahoma into a national champion as a senior team captain in 2000. Now, he's doing the same thing at North Texas.

North Texas went 1-11 in 2015, including a 66-7 loss to Portland State that remains the worst defeat of an FBS school by an FCS opponent in NCAA history. The next year — Littrell's first as UNT's coach — the Mean Green went 5-8. In 2017, they went 9-5 and won Conference USA's West Division. Now they're 3-0 and outscoring opponents 148-56.

“I definitely think we’re a lot further along within our culture,” Littrell said. “They’re bought in. We’ve got a great group. They’re hungry. They believe in it. To me, that’s half the battle.”

And it’s Fine, the diminutive triggerman from Peggs, Okla., who has helped Littrell guide this turnaround every step of the way.

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Fine, who joined North Texas in 2016, is already sixth in school history in passing yards (6,767), fourth in touchdown passes (45), second in completion percentage (62.6) and first in passer efficiency (137.04) through two-plus seasons as the Mean Green's starter. He completed 324 of 511 passes last year for 4,052 yards with 31 touchdowns (all UNT single-season records), earning Conference USA Offensive Player of the Year honors. Now a junior, Fine currently sits fifth nationally with 1,143 passing yards on the season.

His college success is continuation of what he achieved in high school, where Fine set every single-season and career passing record in Oklahoma prep history at Locust Grove High School under coach Matt Hennesy. He became the state's only two-time Gatorade Player of the Year, and his 13,081 career passing yards and 166 touchdowns ranked eighth and fifth, respectively, in national high school history. But with a listed height of 5-10, he received practically no interest as a high school recruit.

That includes Arkansas — 75 miles away from Fine's hometown — which saw firsthand what it missed in him as he completed 24 of 45 passes for 281 yards and two total touchdowns. The Razorbacks weren't the only ones to miss Fine, though; he only received one Division I offer, from Austin Peay.

He thought he'd have a spot at Oklahoma State when offensive coordinator and quarterbacks coach Mike Yurcich told him the Cowboys would come calling "if our guy decommits."

"In my mind I was thinking, 'OK, that’s scholarship.’ You know?" Fine said. "It was Nick Starkel, and I remember when he decommitted (he eventually went to Texas A&M), I just kind of got excited. I think I jumped to a conclusion of, ‘Wow, hey, this might be my break. I might get my lucky break here.’

“And I remember (Yurcich) calling me and telling me that their guy decommitted, and I was like, ‘Yeah? … Yeah?’ Kind of waiting on him to pull the trigger. And he’s like, ‘But, we’re still just going to give you preferred walk-on.’ That was kind of a punch to the gut. It wasn’t a real great feeling.”

As the 2016 National Signing Day approached, Fine's only choice seemed to be a regional Division II program or FBS walk-on.

Finally, the two desperate parties found each other. Littrell needed a quarterback for his first signing class, and when he began to put out feelers in Denton, he was told by Hennesy, whom he trusted from their connections in Oklahoma, that he should look closely at Fine. He watched all of Fine’s film and was intrigued. He dispatched offensive coordinator Graham Harrell to Locust Grove to — as Fine puts it — "make sure I wasn’t 5-8, 145.” North Texas brought him in for a visit. Littrell made an offer, and Fine accepted on the spot.

“It’s just all worked out. Coach Harrell, me and him and Coach Littrell, we’re just a great fit,” Fine said. “It’s just a dream come true. It really is.”

But why did such a successful high school player fall through the cracks?

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“We liked him,” OSU coach Mike Gundy said of Fine earlier this week. “He is a great illustration of a really quality and productive player who gets overlooked because of his size. … He was small, but tremendously productive.

“I think we just thought he was a little bit small.”

Oklahoma State wasn't the only school to think that. Stoops said at the time of Fine's recruitment that he simply couldn't justify offering a scholarship to a 5-10 player. He later called him "an excellent quarterback."

"We’re wrong a lot," Stoops said in 2016. "Guys rating guys are wrong a lot. And it’s hard to know how a guy changes and develops when he gets to college."

Apart from that, many think Locust Grove's offense — which almost never punted and always went for 2-point conversions and onside kicks — may have held Fine back on the recruiting front. If a college coach didn't invest the time to watch his film or invite him to camp, they may have presumed his stats were inflated.

For his part, Lincoln Riley — who became Stoops’ offensive coordinator at Oklahoma in 2015, Fine's senior year of high school — knew a little about the Locust Grove quarterback when he got set up in Norman. It was enough to offer him a preferred walk-on in the recruiting process, but not enough for a scholarship.

“I felt like I hadn’t been here quite long enough to have a chance to go evaluate those guys,” Riley told SN. “I just didn’t want to rush into offering somebody a scholarship that I didn’t know a ton about. And so we knew he was a great player. His film was really, really good. I loved him as a player. Would have brought him here in a heartbeat. But when I knew he was going with Seth ... I was happy about that. I knew what they were doing offensively would really fit him.”

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The big win against Arkansas was just a single step for the 2018 North Texas team, but beating the Hogs in Fayetteville also shows how far Littrell, his coaching staff and Fine have brought the program. It represented UNT's first win over a Power 5 team since 2011 (Indiana), its first Power 5 road win since 1999 (Texas Tech) and its first win over an SEC opponent since 1975 (Tennessee). The Mean Green improved to 3-0 for the first time since 1989. If they win at Liberty on Saturday, they’ll be 4-0 for the first time since 1966.

The win also marks a huge jump for Fine, especially when compared to his first road start against Florida as a freshman in 2016. He was chased and bruised and beaten in a 32-0 loss to the Gators in Gainesville, getting sacked six times and completing just 6 of 22 passes for 66 yards, no touchdowns and an interception.

“We’re light years ahead, as a team, of where we were, and individually, as a player, where I was,” Fine said of the win. “I think I was about a buck-sixty going into that game. This game, I’m about 185. Way more experienced. Me and Coach Harrell were just joking about the dark moments of that freshman year, no really good highlights … I mean, there were just a lot of lows during that season. We just weren’t a good football team.

“You go back two years, coming into Arkansas, we’re more comfortable, we’re more confident, we know we have playmakers, we know we can be special if we just do the right things, put a lot of focus into it and prepare the right way. There’s not a team on our schedule we can’t beat, we feel like.

“And it’s Year 3 in the process. Coach Littrell’s done a great job of turning this culture around and just getting things going in the right direction."

And you can bet Fine is a huge reason the Mean Green are heading that way.