Is Brad Keselowski’s championship a watershed event in NASCAR racing?

Brad Keselowski is a breakthrough champion in a sport where breakthroughs are anything but commonplace.

Does his march to the title signal a new era in NASCAR Sprint Cup Series racing, or is it merely a speed bump in Jimmie Johnson’s road to immortality?

History suggests that the former might be the case.

A first-time champion in a season that produced no first-time race winners, Keselowski is the third driver in the modern era to win NASCAR’s most coveted title within three years of full-time Cup racing. The two drivers who preceded him in that regard have left an indelible impression on the sport.

Dale Earnhardt won the Cup championship in 1980, a year after claiming rookie of the year honors. Earnhardt won six more championships over the next 14 years and ended his career with 76 victories.

Jeff Gordon won the title in 1995 in his third season of full-time Cup racing. Gordon was champion three more times in the following six years and is still writing his legacy. With 87 wins, Gordon is third on the career list.

There is much to suggest that Keselowski, like Earnhardt and Gordon, will be a force in NASCAR racing for years to come.

To team owner Roger Penske, who reveled in his first Cup championship almost as much as Keselowski did, his driver’s breakthrough moment came not this year but last.

After Friday night’s awards banquet at the Wynn, Penske offered that the real turning point for Keselowski was his injury during testing at Road Atlanta in August 2011.

Four days later, with a broken left ankle, Keselowski won at Pocono to start a run that would carry him from 21st in the standings into the Chase for the NASCAR Sprint Cup.

“He beat Kyle Busch,” Penske said, underscoring the significance of that achievement.

The Pocono win was Keselowski’s in more ways than one. It began to turn sentiment in the Cup garage in his favor. Once perceived as a brash, too-big-for-his-britches kid from Detroit who raced too aggressively for the veteran’s liking, Keselowski quickly became a serious threat.

After winning at Pocono, he finished second at Watkins Glen, third at Michigan and first at Bristol — and perception of the young driver among his peers was forever altered.

Not in all quarters, perhaps. Tony Stewart characterized Keselowski’s hard racing against Johnson in the eighth Chase race this year at Texas as “a death wish.” But when he acknowledged the new champion in his banquet speech on Friday, Stewart gave Keselowski his due.

“You showed a lot of us that a not-so-conservative style can lead to great things,” Stewart said. “It’s refreshing. It’s nice to win one being as aggressive as you can be and need to be, and it was nice to see this year.”

Will it happen again? Keselowski has said repeatedly that the Champion’s Week celebrations have fueled his desire to win another title, but that won’t be easy. Change is coming to the sport next year.

First, there’s the new “Generation 6” race car, with much testing to be done before the start of the new season, and much refinement to be done as the season progresses.

Penske Racing will switch from Dodge to Ford next year. From a single factory team with Dodge, Penske will join a Ford armada that includes Roush Fenway Racing and Richard Petty Motorsports. For years, Jack Roush has been the kingpin in the Ford camp.

Penske no longer will build its own engines, but will rely on those supplied by Roush Yates Engines. That’s a radical change.

In addition, Keselowski will have a new teammate, Joey Logano, who comes to Penske from Joe Gibbs Racing. Though it will be a benefit to have a full-time driver in the No. 22 car providing feedback, there’s always an acclimation period when a new driver joins a team.

Somehow, though, there’s a sense that, on the strength of his talent, his focus and his passion, Keselowski will weather the changes unfazed.

Sooner rather than later, we’ll know just how big a sea change his first championship really is.