FORT WORTH, Texas — Double-file restarts and the chance for multiple attempts at green-white-checkered finishes are certainly changing the end of NASCAR races and late-race strategy.

Or is it even strategy anymore?

"It's a crapshoot," Kyle Busch said.

Going into Sunday's race at Texas Motor Speedway, four of the seven Cup races this season have already gone to NASCAR's version of overtime with extra laps. Two of those included multiple restarts after the scheduled final lap.

"It has really made finishes less predictable," four-time defending Sprint Cup champion Jimmie Johnson said. "I don't know if there really even is a strategy now. It's more what the masses do."

The problem this weekend could be getting the race started with rain in the forecast for Sunday. Cup practice was canceled because of rain Saturday, a day after Tony Stewart earned his first pole in five years for what will be his 400th career start.

When Busch pulled onto pit road last weekend at Phoenix International Raceway during another late caution, the only thing that could thwart his dominating run, he got four tires. So did Johnson, with crew chief Chad Knaus figuring the odds were good that there would be more than one try for a green-white-checkered finish.

"It's definitely a gamble, for sure. We knew who we were racing. We were racing the 48 car," said Busch, whose two-second lead over Johnson with three laps left was wiped out by the caution.

Except six cars that took only two tires beat Johnson and Busch out of the pits, then only one restart was needed. Johnson moved up to third in that final two-lap shootout while Busch remained eighth.

"Luckily, it was only a green-white-checkered and not four to go," said Ryan Newman, who snapped a 77-race winning streak by leading the last two laps. "I'm pretty sure that we wouldn't have made it to the checkered if it was (more than one restart)."

Had there been another caution, there could have been up to two more green-white-checkered attempts since NASCAR before this season increased the number of possible retries to three. That would have put Johnson and Busch back into contention for a victory.

If Busch and Johnson had come out of the pits still in front, the No. 18 Toyota and No. 48 Chevrolet would have restarted side-by-side with the double-file system implemented midway through last season.

Adding to those changes already in place, the spoiler effect is likely to come into play in Texas.

Even though the rear spoiler replaced the wing on the back of the cars two weeks ago, the biggest change at smaller tracks was the more traditional look.

The spoiler had minimal impact on racing at the 0.526-mile Martinsville track or even the mile-long Phoenix International Raceway. But that could be much different at the 1½-mile high-banked Texas track that is one of the Cup circuit's fastest.

"I'm hoping it will be a little different so we get an opportunity to shake things up and maybe take advantage of the change," Carl Edwards said.

The only three-time winner at Texas, Edwards hasn't won a race anywhere since the 2008 season finale.

"I think no matter what happens here, there's going to be a verdict on the spoiler," Jeff Burton said. "If we have a great race, if we have a poor race, there's going to be a determination that the spoiler was really good or the spoiler was really bad."

But Burton, the only other multiple winner at Texas (1997 and 2007), was quick to caution that it will take some time for "all the teams to get tuned into" the change.

"If we have a good race here, I think that's a good sign, honestly," he said. "If we have a bad race here, it doesn't necessarily mean that it's bad. ... We kind of just need to run the race and see how the race goes and then make a determination after that. "

Three years ago, NASCAR phased in a new race car that replaced the spoiler with a wing, and the Car of Tomorrow has been used full time since 2008. The wings were taken off last month after several tests, the first with drivers (only four) on the track coming at Texas in January before an open test at Charlotte last month.

"Everybody has to keep in mind, it's just like when we came out with the CoT car initially in the first place, it's an adjustment phase," Stewart said.

Jeff Gordon has gone 36 races — the equivalent of a full season — since his last victory at Texas a year ago that ended a 47-race winless streak. It was his only win in 18 starts at Texas, where he has the only two last-place finishes of his 588 career starts. Homestead is the only active track where he hasn't won.

Gordon was the runner-up at Phoenix last week and third at Martinsville the race before that, leading on the final restarts in overtime in both.

"It's been frustrating for sure," he said. "At the same time, it's encouraging that we're putting ourselves in that position to be able to go out there and possibly win. I think we are heading in the right direction to get ourselves wins and that's what I'm excited the most about. "