NASCAR’s postseason picture just got a fresh face and a more precarious bubble.

Rookie Cole Custer broke through for his first Cup Series victory Sunday at Kentucky Speedway, giving him a sudden jolt of playoff eligibility. The triumph virtually locks him into the 16-driver postseason grid as one of the series’ nine winners this season, even though he sits 20th in the standings — more than a smidgen behind the other provisional qualifiers, who are all among the top 10 in points.

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That shake-up to the postseason stack means that Austin Dillon — who provisionally was in last week at 16th in standings — is now out the next, even with his points rank unchanged. The tentative final playoff qualifier is now 15th-place Jimmie Johnson, who would advance on the basis of points — even after a one-race absence following his reveal of a positive COVID-19 test. Another new Cup Series winner outside that points bracket would put that spot in deeper peril.

To recap and refresh, here are the drivers who have virtually sealed playoff spots (in chronological order by date of their clinching win): Denny Hamlin, Joey Logano, Alex Bowman, Kevin Harvick, Brad Keselowski, Chase Elliott, Martin Truex Jr., Ryan Blaney, Cole Custer.

With 17 of a scheduled 26 regular-season races complete, here’s how the top 12 winless bubble drivers stack up as the playoff cutoff draws nearer.

Aric Almirola (10th in provisional playoff standings, +116 points to the cutline): Blossoming consistency has moved the Stewart-Haas Racing driver out of true bubble territory. A win seems near, but even without it, the points stockpile is an advantageous safety net.

Kurt Busch (11th in provisional playoff standings, +104 points to the cutline): See: Almirola, re: safety net. Kentucky marked his fourth top-five finish of the year and bolstered a substantial points cushion.

Kyle Busch (12th in provisional playoff standings, +89 points to the cutline): Perplexing to see Rowdy without a victory this late in the season? Flash back to 2017, when Busch went winless for the first 20 regular-season races then turned up the wick on a five-win season that came up one position shy of a championship.

Matt DiBenedetto (13th in provisional playoff standings, +68 points to the cutline): Matty D’s third place at Kentucky marked just his second top-five finish this season, his first since Las Vegas in February. It’s a fortifying result, as DiBenedetto placed among the top 10 in both stages for his biggest points payout (43) of the year.

Clint Bowyer (14th in provisional playoff standings, +47 points to the cutline): The nitty-gritty of the playoff bubble starts here. Bowyer was 56 points above the cutline after last week, but his second straight result in the teens has taken some of his points padding away.

William Byron (15th in provisional playoff standings, +30 points to the cutline): Like his Hendrick Motorsports teammates, Byron has a respectable cache of stage points to keep him in the playoff hunt. But as the weeks click away without that first top-five finish of the season, the concerns and pressure could mount.

Jimmie Johnson (16th in provisional playoff standings, +24 points to the cutline): Several races remain for the seven-time champion to solidify his bid for an eighth. As it stands now, Custer’s win pushes Johnson to “last one in” turf, reducing the margin of error moving forward.

Austin Dillon (17th in provisional playoff standings, -24 points to the cutline): An odd late-race spin threatened to derail Dillon’s Kentucky efforts, but the RCR No. 3 team rallied to salvage 13th. Four straight finishes in the teens have actually inched Dillon upward in the series standings, but he’ll need more for playoff security.

Tyler Reddick (18th in provisional playoff standings, -41 points to the cutline): The dynamic rookie has left little doubt about his budding skill, but the deficit created by three early DNFs then a dismal doubleheader at Pocono (finishes of 30th and 35th) make his points path more difficult.

Erik Jones (19th in provisional playoff standings, -42 points to the cutline): That sinking feeling for the JGR No. 20 driver stems from finishes in the back half of the field in three of the last four races. Texas — one of Jones’ better tracks — looms as a potential turnaround point, but a playoff push will need some sustained momentum.

Bubba Wallace (20th in provisional playoff standings, -84 points to the cutline): Wallace’s bid for his first postseason appearance will require more efforts like his ninth-place finish at Indianapolis than a mundane 27th at Kentucky. Barring a rebound, the Richard Petty Motorsports No. 43 bunch may need to rely on some superspeedway magic in the regular-season finale at Daytona.

Chris Buescher (21st in provisional playoff standings, -91 points to the cutline): Another driver in “Hail Mary” territory, Buescher followed two straight top 10s with finishes of 36th, 31st and 20th in the last three races. In the overall points, Buescher is now tied with Custer in 20th place, but the rookie’s Kentucky triumph represents a major leapfrog moment.