Chase Briscoe clinching a Championship 4 spot with his win at Talladega shouldn’t have caught anyone off guard. In this very space, we’d been shouting from the rooftops about his championship potential all summer — and now the 30-year-old Indiana native and first-year Joe Gibbs Racing driver is one race away from cashing in on it.

But Briscoe’s win at a superspeedway — one of his weaker track types — still managed to blow up everybody’s playoff math. He’d entered Talladega as the driver teetering most on the edge between making and missing the championship cut, so his sigh of relief in Alabama immediately became cause for concern among the rest of the playoff field … even the ones who may seem safe at a glance.

Yes, it’s true that as Briscoe was joining teammate Denny Hamlin by locking into the Championship 4, Kyle Larson and Christopher Bell were also building their leads relative to the cutline. Larson went from +35 before Talladega to +36 after, while Bell went from +20 to +37. The gap versus William Byron and company below the line is now wide enough to give both Bell and Larson at least an 87 percent chance each to make the Champ 4, according to our Cup Series Playoff forecast model (which simulates the playoffs 10,000 times using projected Driver Ratings):

That wouldn’t seem to leave much room for anybody else to barge into the final-race picture aside from Bell and Larson — after those two, nobody else is higher than Byron at 7 percent, for instance. But the beauty (or treachery, depending on your perspective) of the win-and-in advancement system is that no points lead is truly safe if you get leapfrogged by a winner coming from below the cutline.

That’s why, in the simulations, there’s just a 77 percent chance that both Larson and Bell race for the title at Phoenix. While there’s next to no chance that neither will be there, there is a 23 percent chance that one of the two makes it and the other is left on the outside looking in:

Basically the only way that would happen is, again, if Sunday’s winner at Martinsville comes from either Byron, Joey Logano, Ryan Blaney or Chase Elliott. But that could certainly happen. Each has won here before in their careers, and Blaney and Byron actually each have a pair of those great, big grandfather clocks in their collections. They’re also all basically in must-win mode, making them especially dangerous.

And if one of them steals the win, the calculations for Larson and Bell change drastically. As the chart below shows, both drivers’ odds of making the Championship 4 would plummet from nearly 100 percent when the Martinsville winner doesn’t come from the bottom four of the active playoff standings, to roughly 50-50 apiece if it does:

Conditional on either a Blaney, Byron, Logano or Elliott win, the model gives Bell a 53 percent chance to be the last driver in, versus 47 percent for Larson. So why the slight edge for the No. 20 over the No. 5?

For one thing, Bell does start Sunday’s race with a slim one-point lead in the points. That may not sound very important, but the margin between Bell and Byron for the final Championship 4 slot during the final lap of last year’s cutoff race at this track was … you guessed it, one point. So that single point could matter a lot in the end. (If they’re tied, currently Larson holds the tiebreaker for his second-place finish at Las Vegas, one spot ahead of Bell as the best of the round for the pair.)

Beyond that, Bell is projected for a slightly higher rating on short tracks in the system that drives the playoff forecast, thanks in part to a better recent form — Bell averaged an 88.9 Driver Rating over the past three short-track races, versus Larson’s 74.7 — even though Larson was ridiculously dominant with a near-perfect 149.6 rating at Bristol in the race directly before that. In terms of average rating on short tracks overall this year, they’re virtually tied, with Larson at 96.5 and Bell at 96.1.

As for Martinsville in particular, the tale of the tape slightly favors Larson … at least on paper. He’s been faster overall in his career at “The Paperclip,” with a better average start (10.5 vs. 15.5), average finish (15.5 vs. 15.5, but buoyed by more top fives), Adjusted Points+ index (148 vs. 135) and a career Driver Rating nearly four points higher than Bell’s (88.0 vs. 84.9). And since the debut of the Next Gen car in 2022, Larson’s advantage has only widened: His Adjusted Points+ index at Martinsville (261) dwarfs Bell’s 157, along with a massive Next Gen-era Driver Rating edge of 109.2 to Bell’s 89.4.

So if we’re looking for a tiebreaker in that coin flip based on overall short-track skill, Larson probably deserves the nod as first among equals going into Sunday’s race. Still, Bell has one important edge that can’t be ignored: He’s won here in a playoff cutoff race before, sealing his 2022 Championship 4 berth with a clutch Martinsville victory — albeit one overshadowed by Ross Chastain’s unforgettable wall-ride.

Most likely, things won’t come down to the direct Bell-versus-Larson showdown in the end. There’s room enough in the Championship 4 for both star drivers — as long as nobody from the bottom half of the Round of 8 crashes the party with a W of their own. The odds of that happening aren’t particularly high, but Martinsville has a way of manufacturing madness when it matters most. Which means both drivers would be wise to keep an eye on each other this Sunday — just in case two open spots suddenly become one.