Ryan: Finale offers five storylines worth watching

• Matt Kenseth's swan song with Roush Fenway Racing is Sunday
• Will Dale Earnhardt Jr.'s up-and-down season end on a high or low note?
• Defending champion and three-time Cup winner Tony Stewart makes his 500th career start

Trading places

HOMESTEAD, Fla. -- Brad Keselowski has built a 20-point lead over the first nine races of the Chase for the Sprint Cup with aggressive plays on fuel strategy and bold calls in the pits.

Jimmie Johnson will inherit that position by default Sunday.

It's been seven years since Johnson arrived at Homestead-Miami Speedway needing a victory to secure a championship, and that's probably a major reason why this 1.5-mile speedway is one of only five tracks that remain unconquered by the five-time champion (who does have four top fives in 11 starts here).

He'll be going for broke in the Ford EcoBoost 400 -- though if the Hendrick Motorsports driver achieves the maximum 48 points for the third time in four races (by winning and leading the most laps), Keselowski still can clinch the championship with a 15th or better.

The Penske Racing driver has promised he won't alter his approach, but crew chief Paul Wolfe probably will be forced to play the averages and won't take many chances on leaving his driver defenseless with worn tires on a restart.

That'll be part of the game plan for Johnson and crew chief Chad Knaus, whose aim will be motivated as much by gambling for a win as trying to make Keselowski and Wolfe feel the heat if the No. 2 Dodge slips deep in the pack.

"Johnson's going to throw Hail Marys, he's going to drive his (butt) off, he's going to try to rip the kid's head off," ESPN analyst Rusty Wallace said. "On the other hand, he's got to be real careful. This racetrack is like Darlington. You have to run right on the wall in turn 3 and 4. One little slip will tear the right side off."

Settling scores amid long goodbyes

This race will mark the end of the line for the much maligned "Car of Tomorrow." It also will be the last chance of the season to exact revenge.

The confluence of those factors could make for another chaotic race full of paybacks that match last week's drama at Phoenix International Raceway.

Though there'll be a championship on the line, the "Boys, Have at It" policy of vigilante justice has been enforced in the past at Homestead. Kevin Harvick wrecked Kyle Busch with impunity in the 2009 finale, and there are plenty of simmering feuds beyond Clint Bowyer vs. Jeff Gordon.

"There's a whole bunch of people that seem to be very angry at each other as of late," Keselowski said.

Combine that with a car that becomes virtually obsolete when the checkered flag falls, and it's a recipe for potential mayhem.

"This is the last race for this particular car," Keselowski said. "I would expect (drivers) to really not care if it got brought back in one piece. The last race on any particular car seems to always have a lot of carnage."

Not all of Sunday's farewells will be acrimonious. After 15 years with Roush Fenway Racing, Matt Kenseth will endure a bittersweet parting before heading to Joe Gibbs Racing to replace Joey Logano, who is sliding over to Penske Racing as Keselowski's teammate in 2013.

Those future relationships also could play a role in the title outcome as Logano's allegiances could be intertwined as much with helping Keselowski as his current team.

Year of Junior

From ending a four-year winless streak in June to missing two races with a concussion last month, the emotional pendulum has swung mightily for Dale Earnhardt Jr. this season.

NASCAR's most popular driver enjoyed his best year since joining Hendrick Motorsports, but his Chase for the Sprint Cup will be remembered as a "what if" after starting with such promise. Still recovering from the effects of an earlier concussion when the 10-race title run began, Earnhardt never hit his stride during the Chase and has posted a best of seventh.

Homestead has ranked as one of his least-favorite tracks and with good reason: He hasn't finished higher than 11th in 12 starts.

But Earnhardt recently said he still feels as if he needs to prove himself to his crew since returning to the seat of the No. 88 Chevrolet, so there'll be plenty of incentive to make one last grab at delivering a transcendent moment and evoke thoughts of what might have been if he'd been healthy.

Smoke signals

The 500th start of Tony Stewart's career seemed destined to be a triumphant milestone early in 2012.

The three-time champion won two of the season's first five races, virtually locking himself into the Chase for the Sprint Cup early and making it seem the path to the title would go through Stewart-Haas Racing for the second consecutive season.

He opened in a loose mood, with a video of him goosing DeLana Harvick going viral from the Chase opener at Chicagoland Speedway.

But rather than coincide with another crowning moment in his career, Stewart didn't realize No. 500 was upon him until he was told because "Smoke" has been so focused on putting out fires that have left his No. 14 Chevrolet slumping for much of the season.

Since winning the July 7 race at Daytona International Speedway, Stewart has seven top 10s in 17 races -- and none higher than fourth. After winning half the races in last year's Chase, this year's playoff has reflected the depth of his slump with fifths at Kansas Speedway and Texas Motor Speedway as the lone highlights.

"A lot of places that we were so good at last year in the Chase, not being good this time around was a little disappointing," he said.

Stewart is a three-time winner at Homestead, including last year when he nipped Carl Edwards for the Cup title. Back-to-back victories at the oval might ease some of the lament of a mostly lost season.

Sideshows!

In case you missed the garage brouhaha at Phoenix, NASCAR sometimes can seem more circus than sport, and there'll be a few goofy story lines and tabloid fodder to follow Sunday:

--With Keselowski feeling "naked" without his cell phone inside the car, how long will it take to bare his soul to the world on Twitter should he win his first championship? Will NASCAR chairman Brian France shove a smartphone into Keselowski's hand before handing him the Tiffany & Co.-designed Sprint Cup trophy?

--It's Dodge's final race for the foreseeable future, and its high-level executives have been in short supply at races since a 2013 pullout was announced in August. Will the manufacturer's major domos be making any high-profile appearances at Homestead? Will their celebration be raucously unrestrained or sheepishly awkward if Keselowski is crowned?

--After playing a live set on the frontstretch before the race, Kid Rock will be answering questions in ESPN's pit studio during the first extended caution period. So one of rock's quintessential hard-partying stars will be performing on a Sunday afternoon just south of Miami after probably spending a night in one of the nation's hippest, hottest nightlife spots?

Surely there are a few salacious details that might be worth exploring on national TV.