The current No. 1 passer in the country, according to QBR, is neither a superstar nor a starter.

Baylor's Seth Russell, the unknown understudy to Bryce Petty, is not out to start a quarterback controversy. Three games into his sophomore season, he's served as both a mop-up reliever and spot starter during Petty's trials with a back injury. He knows this will pay off later.

"All it can do is help with improvement and learning and building my trust," Russell said. "Hopefully I'll build their trust in me that, whenever I get my opportunity, I'll make the most of it."

Neither star nor starter, Baylor's Seth Russell is one of the country's most efficient quarterbacks. Tony Gutierrez/Associated Press

Russell's adjusted QBR of 96.2 puts him right ahead of his teammate Petty (93.6) and Texas A&M's Kenny Hill (92.9), and he's No. 3 nationally in passer efficiency.

"Aw, shoot, that's just numbers," Russell said. "That doesn't mean a whole lot. It's all about going out there, working with the team, getting the 'W.'"

When he's been on the field – nearly 45 percent of Baylor's offensive snaps this season -- there's been zero drop-off in production. In fact, the Bears average a whopping 8.5 yards per snap when Russell is in the game and 7.25 when it's Petty or third-stringer Chris Johnson.

After Petty exited at halftime in the opener against SMU, Russell was put in charge. He was nervous in the days that followed, knowing it was possible he might have to make his first career start.

"What really calmed me down was Coach [Art] Briles talking to us and saying,'This is a time to inspire people,'" Russell said. "He said just because you're a backup doesn't mean you can't play. It was definitely a burden taken off me and a sense of relief."

Petty was officially ruled out hours before kickoff against Northwestern State and Russell got his shot. He earned Big 12 co-Offensive Player of the Week honors after throwing for 438 yards and accounting for six touchdowns in one half of play in a 70-6 win.

"He was exceptional in how he handled himself and the decisions that he made," Briles said last week. "That's the thing that I told him I was proud of."

Briles said there were two plays in which Russell made the wrong decision against Northwestern State. That's two too many by his standard, but not bad for a first start. Last Friday, as Petty's backup once again, Russell played two series and led two touchdown drives.

"Whenever I got out there, I have to have the mindset that it's a win-or-lose game," Russell said. "It's the mindset that, even if we're up 50 points, you always have something to prove."

Like Petty, Russell's road to Baylor was paved by a coaching change. He'd committed to Kansas and then-coach Turner Gill in the summer before his senior season at Garland (Texas) High School.

When Gill was fired at the end of the year, Charlie Weis came in and brought former Notre Dame quarterback Dayne Crist with him. Russell says his scholarship offer was not pulled, but he had to reconsider his decision.

"It definitely tested my faith," he said. "I talked to the coaches there and gave them the best opportunity possible, but when I went up there I didn't feel like it was the right fit. Baylor opened up their arms and I felt like it was the right place for me."

Coincidently, Baylor had a scholarship open up when Robert Griffin III went pro early. Kevin Murray, the Dallas-area quarterback coaching guru and former Texas A&M quarterback, worked with Russell in high school and said he couldn't get any other Big 12 programs to bite on taking him. He played in a system at Garland that didn't showcase his passing ability.

Baylor was the best fit, Murray said, because Briles and offensive coordinator Philip Montgomery recognized Russell had a high ceiling to match unusual athleticism.

"I don't think anyone outside of Waco understands how good this kid is," Murray said.

They'll start to find out soon enough. As Baylor enters Big 12 play, its backup knows he's ready for whatever comes next. He must be rooting for a few more blowouts and fourth-quarter snaps, right?

"Aw, shoot, I'm just happy if we get the win," Russell said. "Obviously I want to play, but if we get the win, that's all the matters."