Arizona's Khalil Tate spins free of defenders and gains the final 31 of his 327 rushing yards for the game which set an FBS record for quarterbacks. (0:37)

TUCSON, Ariz. -- College football learned the name Khalil Tate right about the time his opponents did.

"Well, I didn't even know his number if I'm going to be honest," Colorado's Ryan Moeller said three weeks ago. "We were expecting a different guy to back up and someone else came into the game."

Once he was in, Colorado coach Mike MacIntyre had a simple plea.

"Would somebody please tackle No. 14 for Arizona?"

Tate, coming off the bench, decimated the Buffaloes. He rushed for 327 yards, a record for a quarterback, and four touchdowns. He added another 142 yards through the air and another score.

Suddenly, #Pac12AfterDark had its newest must-see star.

And it almost never happened.

When Arizona quarterbacks coach and co-offensive coordinator Rod Smith first watched Tate's high school film, he had mixed emotions. On one hand, he was blown away by his talent and knew he would be a good fit in the Wildcats' system. On the other, Tate went to famed Serra High in Southern California, which Smith knew to have a strong pipeline to USC.

"I was like, 'Do we even have a shot at this kid?'" Smith said. "Will he even give us a sniff?"

Several programs recruited Khalil Tate as an athlete, not guaranteeing a chance to play QB. Tom Hauck for Student Sports

Tate succeeded Jalen Greene as the quarterback at the powerhouse school. They grew up around the corner from each other, and he paid close attention to Greene's recruitment. USC signed Greene as a quarterback but eventually moved him to receiver. When Tate started being recruited by then-USC coach Steve Sarkisian, he was told they wanted him as an athlete. Then, when Clay Helton took over, he was told they saw him as a quarterback.

As a senior at Serra, Tate rushed for 2,130 yards and passed for 2,036 and ended the season as ESPN's No. 10-ranked dual-threat quarterback in the country.

"Being so close to Jalen. I kind of knew that I wasn't sold on it," Tate said. "Someone I grew up with, one of my best friends, he went to play quarterback and then so-called switched. So I'm like, 'I'm not too sold on that.'"

Among the other schools he considered was Texas A&M, but after watching Kyle Allen and Kyler Murray transfer and the quarterbacks coach leave, that didn't smell right either. As his recruitment played out, it became clear that Arizona, which made it very well known it wanted him as a quarterback, was the right fit.

"Khalil is a pretty sharp kid," Smith said. "He can smell through someone's B.S. He was good and stayed true to his word, and we did too."

Arizona coach Rich Rodriguez was sitting in his office on the Monday afternoon prior to the Colorado game when Tate came to visit.

Rodriguez has an open-door policy, so this wasn't necessarily outside the norm, but he could tell right away something weighed heavily on Tate's mind.

The sophomore QB wanted to play and wanted to see what he could do to make that happen. To that point, Tate's season hadn't gone according to plan. He sprained his shoulder in the season opener against Northern Arizona, and though he played the next week against Houston, he probably shouldn't have. He didn't play the next two games or practice the next three weeks as he worked his way back to full health.

play 0:32 Tate dazzles with 76-yard TD run QB Khalil Tate, who became Arizona's starter just two weeks ago, runs for his FBS-best third touchdown of at least 70 yards.

Rodriguez's message was honest and simple: Practice better. Show up during practice healthy and ready. The coaching staff knew he was talented, Rodriguez told Tate, but to justify more snaps, they needed to see him perform during the week.

"It was hurting him because he thought he could help us win, which I can appreciate," Rodriguez said. "... That week after that he was possessed in practice. He was healthy. He was showing everything."

There was still no way Rodriguez could have predicted what happened in Boulder that week. It would have been unreasonable to expect his backup quarterback to turn in one of the best performances by a quarterback in college football history.

In fact, it took a fluky set of circumstances for Tate first get on the field against the Buffaloes. Starting quarterback Brandon Dawkins took a late hit out of bounds from a Colorado defender and needed to come out. The injury wasn't serious -- he was fine to enter a short while later -- but it provided Tate the opportunity he needed.

"I was watching and I was zoned in," Tate said. "When he got hurt, it was unreal because it happened so fast. Rich Rod said, 'Come on out.'"

The Wildcats fumbled two plays later, but after their defense forced a three-and-out to get the ball back, Tate's magical game really began. He kept it on a zone-read on the first play of the next drive and went 58 yards for a touchdown. He ran for a 28-yard score on the following drive.

"About [Tate's] fourth time out there," MacIntyre said, "I was like, 'Crud, I don't think we'll ever get this kid down.'"

Arizona scored touchdowns on six of its first seven drives with Tate at quarterback, and by the time it was over, he had a record and finished the game with a perfect QBR of 100. More importantly, Arizona won 45-42.

"[Dawkins] was OK, but this guy is going crazy," Rodriguez said. "Why am I going to take him out? It's like when you have a guy hitting all the 3-pointers. You have to leave him in. Brandon was ready to go, but Khalil took the job and literally ran with it."

In the month of October, Tate, who turned 19 on Monday, has been without question the most productive player in college football.

A week after his sensational breakout game against Colorado, he ran for 230 yards and threw for 148 and racked up three more touchdowns in a 47-30 win against UCLA.

"That young man is dynamic, and he changes the game," said UCLA's Jim Mora after Tate destroyed the Bruins' defense. "You have to defend him every single play. He makes you miss, and when he gets in the open field he is spectacular. He has had two tremendous games in a row. We put all our energy into stopping him, and we did not get it done."

And last week, he led the Wildcats to a 45-44 double-overtime win against Cal. It was a tougher outing for Tate who only accounted for 303 total yards and three touchdowns, but ran for over 100 yards in the first half making it five straight halves he eclipsed that number. His presence is also opening things up for other Wildcats. Running back Zach Green ran for 130 yards and the go-ahead touchdown in overtime with many of his yards coming off zone-option plays.

"Obviously, pump the breaks a little bit because he's only started a couple games," Rodriguez said. "But he's taken advantage of his chance, and that's cool to see."

What Tate was never supposed to do was play early in his college career.

Tate has close to 700 yards rushing in the month of October alone. Russell Lansford/USA TODAY Sports

When he arrived in Tucson last year, he was just 17 years old and raw fundamentally. Plenty of kids his age were still juniors in high school. The Wildcats had a two-year starter returning in Anu Solomon, plus a redshirt sophomore in Dawkins. The plan was to let him redshirt, but by the fifth game of the season the Wildcats were so decimated by injuries they had no choice but put him in.

Tate came off the bench in losses to UCLA and Utah and made his first career start as Arizona hosted USC, the eventual Rose Bowl champion. None of these games went well for Tate, or the Wildcats. He wasn't ready and the team went on to lose its first eight Pac-12 games of the season.

Looking back, though, Tate says taking his lumps last year made the past three weeks possible.

"It helped, because I knew what it was like to come off the bench," he said. "I tried to use it to my advantage. Say I would have redshirted last year. I wouldn't have known how to come in against Colorado because it would have been my first time. It really helped a lot getting those few reps."

Now, in three weeks' time, Tate has 694 yards rushing this month -- 100 more than the next best player in the country (Wisconsin's Jonathan Taylor), and his QBR (99.5) is unmatched by any quarterback. And despite starting just two games, Tate still has 23 more rushing yards this season (780) than Penn State's Heisman Trophy front-runner Saquon Barkley (757). On his seven touchdown runs this year, he's averaging 57.1 yards per carry and has a touchdown run of 70-plus yards in the past three games.

Tate's smashing debut has drawn comparisons to other Rodriguez protégés such as Pat White at West Virginia and Denard Robinson at Michigan. They're all different, of course, but Rodriguez said Tate doesn't have the same pure speed as White or Robinson. It's his rushing numbers that have brought national attention, but it's what he can do with his arm as well, Rodriguez said, that makes him especially unique.

"He can throw it 70 yards, but some guys who can throw it 70 throw a 20-yard pass like he's throwing it 70," Rodriguez said. "He's got as a good a touch on the deep ball as anybody I've had. He has a natural throwing motion."

Now the Wildcats' season gets a lot tougher. Arizona (5-2, 3-1 Pac-12) hosts No. 15 Washington State (7-1, 4-1) on Saturday followed by a trip to No. 21 USC. But after a month when Tate was launched into college football stardom and left conference coaches in awe, it was right on script for at least one future opponent.

USC defensive lineman Oluwole Betiku was in Tate's class at Serra.

"I've seen it before, so I'm not impressed," Betiku said. "I saw him do it all through high school, so I'm just seeing Tate be Tate. They finally gave him the ball, and he's doing what Tate does."