Standing on the Rose Bowl sideline that September afternoon when Utah was losing to UCLA, quarterback Brian Johnson wondered what he ever was thinking when he chose to sit out the season.

Two years later, he knows.

Johnson understands perfectly where all that advice was coming from, now that the Utes are 12-0 and preparing to play Alabama in next Friday's Sugar Bowl.

The story will remain part of the lore of Utah's return to the Bowl Championship Series, how Johnson would have missed all of this -- and who knows if it would have happened without him? -- if not for the knee injury that served to extend his college career.

"It's very rewarding," Johnson said, "just because of the road we've traveled, the adversity not only I've been through, but we've been through as a program. We've experienced some of the highest of highs and some of the lowest of lows. It's been a true full-circle ride."

So here they are, back in a BCS game, just like four years ago when Johnson was a 17-year-old freshman backing up Alex Smith. Since then, Johnson has played through his first season as a starter that ended with his knee injury in the 10th game, the redshirt year, a junior season when a shoulder injury cost him parts of four games and limited him the rest of the way, and now this: a 12-0 season, with another game to play.

Somebody obviously knew something in the summer of '06. Maybe offensive coordinator Andy Ludwig did not quite envision all of this, but he projected an '08 lineup that included receivers Brent Casteel, Bradon Godfrey and Freddie Brown and a veteran offensive line. "Look at your senior year," Ludwig told Johnson. "You're going to be loaded with playmakers."

As much as he had worked to return to the field, nine months after his injury, Johnson soon recognized the value of waiting. It may have been the best call of Ludwig's four years with the Utes. During this deferred senior year, Johnson became even more of a team leader, while producing the winning drives in signature victories over Oregon State and Texas Christian.

"Brian kept it all on his shoulders and we got through a couple tough games, just because he's a great leader," Casteel said.

"He just handles everything with poise," said Stacey Johnson, whose admiration of his son goes beyond football. He's proud of the way Brian has matured as a team spokesman (coach Kyle Whittingham requires the starting quarterback to attend a weekly news conference) and last spring completed a degree in mass communication.

Johnson's football success is no surprise to anyone at Robert E. Lee High School in Baytown, Texas, near Houston. Having transferred from his hometown school in Crosby, about a dozen miles away, Johnson joined Lee's remarkable run of developing major college quarterbacks. But that was only after spending his junior year as a receiver and defensive back, while the Ganders were quarterbacked by future Iowa star Drew Tate.

Johnson's most memorable moment that season came when he broke his two front teeth while making a tackle. A quick visit to the emergency room enabled him to play in the second half, and a day in the dentist's chair restored his smile in time for the homecoming dance. Yet the experience convinced him he would be "nothing but a quarterback," according to his father, who laughed while retelling the story.

The next spring, when Texas high schools were practicing, then-Utah quarterback coach Dan Mullen scouted Johnson as a potential replacement for Smith in a spread offense. Mullen liked Johnson , but coach Urban Meyer needed to see game film before committing to him. The proof came early that season when Johnson delivered "ridiculous" numbers, by his account, in a game that Mullen witnessed, then brought back the film to show Meyer.

Johnson accepted the scholarship offer and was part of the '04 Fiesta Bowl season, only to have Meyer and Mullen go to Florida by the time he was ready to follow Smith as Utah's starter. Johnson thrived in Ludwig's system as a sophomore in 2005, ranking fourth in the country in total offense, but the Utes were only 5-5 when his season ended.

Then, after Brett Ratliff led the Utes to an overtime upset of Brigham Young and an Emerald Bowl rout of Georgia Tech, Johnson spent a lonely offseason of rehabilitation, followed by the redshirt year. "That was a tough time," he said.

It became even tougher in '07, when he took the field for the first time in 21 months and was knocked out of the opener at Oregon State with a separated shoulder just before halftime. "That was kind of a 'why me?'" he said. "I really didn't understand that, because I had worked so hard, just to try to get healthy."

Before Johnson resumed his starting role, the Utes had lost three of four games and Whittingham's future was being questioned. Since then, Utah is 20-1.

This season, Johnson has completed 68 percent of his passes for 2,636 yards and 24 touchdowns. His numbers do not quite match those of his sophomore year, but the team's record is considerably better.

As he leaves the program following the Sugar Bowl, Johnson's legacy will be built around his perseverance, his winning nature and his prescience in looking ahead to the possibilities of this '08 season.

"Brian is a fighter, I'm a fighter," said Casteel, who came back from a major knee injury of his own. "His injury definitely inspired me to get better and do more."

Judging by the Utes' performance, Johnson's influence was contagious.

kkragthorpe@sltrib.com