MIAMI, Fla. -- Clearly, Jeff Gordon hasn't met Yogi Berra.
After Jimmie Johnson won at Phoenix last weekend, Gordon declared, "It's over," about the Chase for the Nextel Cup. Gordon is 86 points behind with one race left.
But as Yogi said so eloquently years ago, "It ain't over till it's over."
Gordon should keep that in mind when the green flag waves Sunday in the Ford 400.
Upsets and surprising comebacks really do happen in sports. It's one of the reasons fans love to watch. Just in the last few months, we've seen some shockers.
Upset? How about Appalachian State beating Michigan in college football.
Shocker? Kansas is 10-0. And we're talking football, not basketball.
Comeback? The Boston Red Sox were one game from elimination in the playoffs, down 3-1 to the Cleveland Indians. The Red Sox won the next three to claim the American League pennant before winning the World Series in a four-game sweep over Colorado.
And we've seen it this year in racing. For the second consecutive season, Top Fuel driver Tony Schumacher came from behind to win the NHRA championship on the last pass in the final event.
Schumacher was 67 points back in fourth place going into the last race. He knows better than anyone what can happen Sunday at Homestead Miami-Speedway.
"I think too many people are saying it's over, but I'm not one of them," Schumacher said. "Our U.S. Army team is vivid proof that the unpredictable can happen. If a champion driver like Jeff Gordon is in mathematical contention, you don't bet against him."
The odds are against Gordon catching his teammate. Johnson has to finish lower than 18th for Gordon to have any shot. And no Cup driver ever has overcome an 86-point deficit in the last race.
But sports competition is filled with moments when teams and individuals bucked the odds and came out on top. Normally, you have to hope your opponent makes a mistake to give you an opening.
In this case, it can happen without Johnson doing anything wrong. The X-factor is a 3,400-pound race car with hundreds of moving parts and pieces of machinery that can fail at any moment.
For 400 miles over 267 laps, countless things can go wrong. It's nerve-racking for Johnson. Every little noise he hears all day in the car could be the one that ends his day.
So what specifically could go wrong? Here are four ways Johnson could lose the championship and Gordon could claim his fifth title:
• Engine failure -- This doesn't happen much at Hendrick Motorsports. The organization has the best engine builders in the business. And it's even less likely this weekend for Johnson because crew chief Chad Knaus and his team will set up the engine to place as little stress on the motor as possible.
But even the best engines can suffer a failure from high RPMs over an extended period. All it takes in a bad piston, a broken connecting rod, one cracked cylinder head, etc.
• A flat tire -- A good team like the 48 usually can overcome the problems of a tire going down, but sometimes a bad tire causes a more serious situation.
A blown tire often forces the car to slam into the outside wall, damaging the car beyond repair. Even if the driver keeps the car off the wall, the flapping rubber from the tire can damage the quarter panel before the driver can get the car back to pit road.
• Pitting at the wrong time -- Johnson could get caught a lap down late in the race if he had to pit under green, then a caution came out before the other leaders pitted. It's a weird quirk of racing that happens to the best of them.
• Wrong place, wrong time -- No matter how good you are behind the wheel, a crash can happen in front of you that you can't avoid.
Johnson probably will run near the front most of the race, so the chances of getting caught up in a multicar crash are diminished.
But restarts are the biggest concern. Lapped cars line up inside of the lead-lap cars, so slower cars are running side-by-side with the leaders.
Johnson might restart sixth in race position but 12th on the track. And one lap later Johnson might find a lapped car sideways in front of him that he can't escape.
Restarts are inherently dangerous. Look what happened at Atlanta when leader Denny Hamlin ran out of fuel on a late restart. Martin Truex Jr. was headed for a top-5 before making scrap metal on his car on that restart.
All these scenarios could cause Johnson to finish lower than 18th. Gordon said he would hate to win the title because Johnson had problem at Homestead.
It's all part of the game, Jeff. If bad luck befalls Johnson, you seize the moment and steal the title.
Terry Blount covers motorsports for ESPN.com. He can be reached at terry@blountspeak.com.