You can’t avoid complicated with anymore, and two of its newer rules could potentially put huge wrinkles into the sport’s title races—wrinkles that could determine or de-crown a champion on the spot.

Some of the biggest changes to NASCAR in recent years have been in the overall championship format, as the organization has tried to make its car racing series more like a ball sport. The effort has made for some complex rules.

The first of the changes came right before the , last season. That change was the addition of an “encumbered finish” to the rulebook: a form of unofficial disqualification that removes all the benefits of a driver’s finish while not altering the official finishing order.

The second was the introduction of a “repair clock” for 2017, which took garage repairs out of the equation in most situations. The repair clock gives teams a certain amount of time to get a wreck-damaged car back on track at a certain speed, and forces cars that go into the garage after a wreck to stay there.

Those rules, while seemingly harmless in the big picture, could completely alter the championship both during and after the final race of the season. NASCAR knows that, but it’ll keep consistent with the rules no matter what happens.

How NASCAR Titles Are Decided

As of this race season, all three of NASCAR’s top national touring series use a knockout playoffs format to decide the champion. The numbers of drivers and races vary per series, but we’ll use the Monster Energy NASCAR Cup Series as an example throughout this post.

Here’s how the playoffs, the last 10 races of the season, work:

for the Cup Series playoffs, based on points and wins. A non-encumbered win during the regular season automatically qualifies a driver for the playoffs. , the. A win by a playoff driver in this round automatically moves them to the next. The rest of the spots are decided by points. . , the . A win by a playoff driver in this round automatically moves them to the next, and the other spots are decided by points. . , the . A win by a playoff driver in this round automatically moves them to the next, the other spots are decided by points. .The in one final race at Homestead-Miami Speedway. The .

The event at Phoenix Raceway this weekend will be the ninth race of the Cup Series playoffs. Currently, Kyle Busch, Kevin Harvick and Martin Truex Jr. all have automatic spots in the “championship four,” as NASCAR likes to call it. There is one spot remaining, and it will be decided this weekend.

Any of those four drivers could win the championship, but any of those four drivers could also have the championship ruled away. Let’s talk about how.

In The Instance Of A Huge Wreck

In regards to the repair clock, NASCAR has no “what if” rules in place. That means a big wreck could end the championship right there on track, with results that could surprise the casual viewer.

On a call, Jalopnik laid out what a NASCAR spokesperson called a “doomsday” scenario: If all four championship contenders get into a wreck that sends all of them to the garage, in any series, is there a backup plan?

There isn’t.

The new repair rules mean that if a driver goes into the garage as a result of crash damage, that driver won’t come back out during the race. The title picture automatically gets weird right there: Before the repair rules, this would have created a thrashing of race cars in the garage, with the first team back out likely winning the title. It never happened that way, but could have.

Under the new rules, all of those teams would be done for the day. And, without a backup plan, NASCAR would use its general race rules that are already in place to determine the title winner: In the case of a caution before the final lap of the race, the finishing order is determined by running order at the end of the last completed lap. That differs from how NASCAR sets the field, which is by the previous timing line—an arbitrary point on the track where cars are scored.

That’s how NASCAR would decide the title, should “doomsday” happen before the last lap, when results would instead be determined by running order at the time of the caution. But calling it “doomsday” doesn’t mean that NASCAR is all but ruling out the possibility of the four drivers wrecking.

“It’s not that far fetched,” a NASCAR spokesperson said. “I doubt it would happen early, but if you look at the last few years, the championship four have been pretty much stacked together at the end there.

“We’d go to the previous [completed lap], and if it’s the white flag, we’d use all available resources [to determine the title leader at the time of caution].”

Should the title decision come down to that determination in a caution outside of the last lap, the champion may not be decided by running order at the time of the wreck. The champion would be the one who was out front at the start-finish line at the end of the last completed lap, which could be vastly different.

( A NASCAR spokesperson originally said the finishing order would be determined by the previous scoring loop should this wreck happen before the last lap, which is how NASCAR determines running order for a caution. NASCAR has since corrected this, saying the finishing order would be determined by the running order at the end of the last completed lap.)

The spokesperson said even if there was strong backlash against this type of championship ruling, he doubts the sanctioning body would look at changing the rules that govern individual races the following year.

“As far as the nitty-gritty rulebook rules—the damage policy, beneficiaries, restart rules—those are all going to be consistent race by race,” he said. “I find it hard to believe that we would change it if it was unpopular, but we’re always wanting to make it the best for the fans.

“So, if it was overwhelmingly negative and we felt like it was a necessary thing to do under that unique circumstance, we would probably look at it. But my gut tells me that we’d try to stay as consistent as possible when it comes to the rules, regardless of whether it’s race one or race 36.”

In The Instance Of An Encumbered Finish

Encumbering finishes is also part of the rulebook that applies to all 36 races (at least, in the Cup Series—the lower national levels have fewer races). Should a finish by one of the remaining championship contenders be encumbered in the Homestead race, things could get ugly.

An encumbered finish, which allows a driver to keep a win or finishing position they achieved in a race, takes away all benefits of that win or finishing position. NASCAR encumbers a finish automatically if a car gets a “Level 1” or “Level 2” penalty after the race. NASCAR senior vice president of competition Scott Miller told last year that in order for an infraction to lead to an encumbered finish, it has to “be egregious, it will be deliberate, it won’t be an accident.”

Here are the details on L1 and L2 penalties, which lead to encumbered finishes:

Concerns rules around minimum heights and weights, the Laser Inspection Station NASCAR uses for inspections, gear ratios, and lug-nut violations. NASCAR checks lug nuts at the end of races, and deems a violation to be “flagrant” if only 17 or fewer of the 20 total lug nuts on the car are properly secured. NASCAR describes L2 issues as involving “more egregious infractions concerning tampering with the three ‘no man’s land’ technical areas of tires, engine and fuel.” Safety violations, the use of telemetry or traction control, and breakage of testing policy are areas in which L2 penalties can occur.

If any of that happens, the finish is encumbered.

Any other time of the year, an encumbered finish would just have those “major championship implications” we’re all used to hearing about for an individual driver. But if a championship contender—the title winner, let’s say—gets encumbered after the race at Homestead, the entire title battle is in jeopardy.

Before we get to how NASCAR would rule an encumbered championship finish at Homestead, it’s important to note NASCAR as an entity is strongly against taking wins away. That’s why encumbered finishes exist: As the NASCAR spokesperson confirmed, the sanctioning body has long been a proponent of the old “fans should see the winner at the end of the race” mentality. NASCAR didn’t want fans to read about a different winner due to disqualification in papers the next day, especially after they’d paid to see a race, and NASCAR still doesn’t want that to happen.

But the encumbered finishes make for a weird situation at Homestead. Any other time, the winner would stay the same and not get the points. If a title winner gets encumbered at Homestead, though, it would mean the points benefit of winning the title would disappear as well. That means a change in winner, if we take the rules exactly as they’re written.

And is that what NASCAR will do?

“Yes,” the spokesperson said. “If we do find an infraction that is an L1 or an L2 penalty, we will enforce the rules and do what we have to do. Obviously, that’s not something we want to do, and I think the teams are aware that we will make that tough decision if it comes down to that.”

NASCAR’s taking precautions in hopes to keep it from coming down to that, starting this week. All eight cars that remain in the championship will go to NASCAR’s Research and Development Center for a pre-Homestead inspection, since the five drivers who aren’t locked into the championship race all have a shot at making it in Phoenix.

The R&D Center, on any other given week, is only for post-race inspections and certifying new race cars for safety prior to teams entering them into races.

This unusual trip to R&D will be to try to keep teams from tampering too far with cars before Homestead, , so that NASCAR won’t have to encumber anyone. The cars will be “built and ready to go” for the race when they get there, the spokesperson said.

“We’ll have all eight teams into the R&D center and inspect the cars,” the spokesperson said. “We’ll certify some of the parts like the engine, so that when we give them back, they can’t mess with them.”

The spokesperson called it a system of “checks and balances” with an extra layer of preventative measures that NASCAR doesn’t have any other week.

“Once we get to Homestead, it’s the same,” the spokesperson said. “We’ll have pre-qualifying inspection, like we always do, and we’ll have pre-race inspection like we always do.

“After the race, we’ll check the lug nuts prior to [the championship drivers] getting to the stage so the lug nuts will be good to go. They’ll celebrate, then we’ll do what we typically do at the R&D center at the track. We’ll do a full teardown on the champion at the race track.”

If a car doesn’t meet lug-nut requirements, it’ll be an immediate encumbered finish before the champion reaches the stage. But NASCAR isn’t too worried about lug nuts or any infractions that would encumber a championship finish, because the spokesperson said he “think[s] teams are aware that we don’t want them to sully up our championship show.”

“I think fans should feel comfortable that [the driver] they see celebrated post race will be the champion, because teams realize that we’re serious about it,” the spokesperson said. “But if we have to make that decision, we will.”