Once upon a time, NASCAR’s star in the sports world’s firmament dimmed perceptibly about the time tree leaves began turning from green to their kaleidoscopic autumn hues.

The ear-drumming thunder of tuned-to-the-max stock car engines didn’t subside. It just became muffled in the cumulative roar of NFL and college football crowds raising the decibels from the southeastern tip of Florida to the northwest corner of the state of Washington.

Then came “The Chase.”

A revolutionary 10-race “playoff” concept that initially received a lukewarm reception from hard-core fans in 2004 promptly gave NASCAR a grand stage for a climactic Sprint Cup championship battle in fall months.

Tinkering with the format since its inception improved the product to a point, during early evening hours Nov. 20, 2011, at Homestead-Miami Speedway, that the overwhelming consensus of exhilarated Ford 400 witnesses was, “How can you possibly top that?”

Maybe they can’t. But five-time Sprint Cup champion Jimmie Johnson and brash young challenger Brad Keselowski will try Sunday in Phoenix and next Sunday at Homestead to create a comparably mesmerizing slice of history.

Here’s a bare-bones refresher on the unimaginable 2011 plotline:

Charismatic Carl Edwards arrived at Homestead with a three-point edge over tenacious two-time Sprint Cup champion Tony Stewart. Edwards would clinch the championship if he finished the Ford 400 in front of Stewart. Stewart’s only assured path to the title was to win the race.

Edwards collected 44 points in the finale: 42 for finishing second, one for leading a lap, and one more for leading the most laps. Stewart earned 47 points: 43 for first place (by a margin of 1.3 seconds), one for leading a lap and the three-point victory bonus.

Season/Chase totals: Stewart 2,403, Edwards 2,403. Tiebreaker: Stewart’s five 2011 victories to Edwards’ one. Improvement by one position in any one of 36 races would have resulted in Edwards’ coronation. Exulting champion Stewart captured the pinch-me euphoria of drivers, teams and fans alike: “Oh, my God! Are you kidding me?”

Dale Jarrett, who clinched his own 1999 Cup championship on Homestead’s 1.5-mile oval but in relative comfort, watched the breathtaking 2011 theatrics play out from ESPN’s telecast booth.

“You could write a script that’s almost Hollywood-esque,” he said, “and it became a reality.” He said telecast partners Alan Bestwick, Andy Petree and he “just kept looking at each other and shaking our heads over what we were seeing and how fortunate we were to be a part of it from the TV side.”

This was a winning 60-yard “Hail Mary” touchdown on the final play of a Super Bowl, a walk-off, grand slam in the bottom of the ninth of Game 7 of a World Series.

Jarrett recalled pre-Chase years when a driver nurtured a substantial points lead into October and the sport “would get really lost” in terms of national spotlight and media coverage. Today, he said, “The Chase keeps the sport in focus and in the forefront.”

Race report newspaper headlines, often found buried on inside pages if a Dale Earnhardt or a Jeff Gordon or a Jarrett had dispatched all challengers in anticlimactic points battles, have reclaimed Page 1 prominence.