OPINION

By Reid Spencer

updated 5:23 p.m. ET Oct. 21, 2008

After Jimmie Johnson's dominant win Sunday at Martinsville, you'll find the story of the 2008 Chase for the NASCAR Sprint Cup in the obituary pages of most publications.

If the Chase were a T-ball game, the mercy rule would apply. If the Chase were a political convention, Johnson would win the title by acclamation.

Before you dub this year's Chase the 2008 Foregone Conclusion, however, stop for a minute to remember the 2004 Boston Red Sox, who were written off after losing the first three games of the American League Championship Series to the New York Yankees -- and came back to win four straight.

It might be wise to remember Jean Van de Velde, who came to the final hole of the 1999 British Open with a 3-shot lead, only to record an absurd triple bogey. He lost the championship To Paul Lawrie in a playoff.

Admittedly, Johnson's closest pursuers, Greg Biffle and Jeff Burton, will have to climb Mount Everest in a snowstorm to wrest the title from the No. 48 team, but that doesn't mean it can't happen.

With all they've accomplished in winning back-to-back championships in 2006 and 2007, Johnson and crew chief Chad Knaus still have one more thing to prove, that they can win as heavily favored front-runners. The team known for its resilience in the face of adversity must now prove it can avoid the temptation to sit on a lead.

With four races left, Johnson leads Biffle by 149 points and Burton by 152. Fourth-place Carl Edwards — 198 points back — is the only other Chase driver within 200 points. If Johnson posts an average finish of fourth in the next four races, he locks up his third straight championship, even if Biffle wins all four races and leads the most laps in each one.

In 2006, Johnson's average finish in the final four races was 3.75 (three seconds and a ninth); in 2007 it was even better: 2.5 (three wins and a seventh). The difference is that, in both 2006 and 2007, Johnson was still behind after a victory at Martinsville.

In 2006, he was third in points, trailing Matt Kenseth by 41. In 2007, he was second, 53 points behind teammate Jeff Gordon. In each case, Johnson took the championship lead at Texas.

This year he's defending, not chasing. And after Sunday's race, we got our first glimpse of outcome thinking from the two-time champion, when he was asked whether it was time to start considering the prospect of tying Cale Yarborough's record of three straight championships.

"Maybe it is," Johnson said. "I'm going to have to answer those questions one of these days, aren't I?"

Probably, but not yet. Johnson himself knows the danger of thinking too far ahead.

"(Saturday) in practice I knew the 24 (Gordon) was the best car, and I was kind of content being second fastest, felt good about things, was worried about the 99 (Edwards), 31 (Burton) and 16 (Biffle)," Johnson said after Sunday's race. "I thought, 'All right, we're better than those guys. We're good.' And Chad was cracking the whip on me.

"He was like, 'Dude, it doesn't matter. Why are you worried about those guys? We need to go out and make sure that we're the best car on the track. Let's not change what we've done. Let's stay focused on being the best car.' I looked at him and said, 'Thanks. I needed that.' If I start worrying about protecting something, I'm going to make mistakes, and he is as well."

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That doesn't mean it's easy to stay focused. Not when NASCAR is scheduling a special teleconference with Yarborough the day after the Martinsville race to talk about Johnson's bid to tie the record of three straight championships Yarborough won from 1976 to 1978.

"The handwriting's on the wall," Yarborough said. "It's gonna happen."

Wait a minute. There are four races left, 40 percent of the Chase. True, Johnson controls his destiny, but in racing, that destiny is inextricably interwoven with the actions of 42 other drivers.

One of the most intriguing aspects of motorsports is the delightful randomness of events, where one mistake can turn order into absolute chaos in a fraction of a second. There is no defense against the sudden swerve of a car into your space on the racetrack.

So before you concede the title to Johnson, realize that he has miles to go before he sits at the head table in New York City — 1,714 miles at a minimum — and it's almost a given that the final four races won't simply be Sunday drives for the would-be three-time champion.

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