Titles in all three of IMSA’s WeatherTech SportsCar Championship classes are up for grabs Saturday night at Petit Le Mans.

The prized Drivers’, Manufacturers’, and Teams’ championships in Prototype, GT Le Mans, and GT Daytona championships will be settled, and the Tequila Patron North American Endurance Cup crowns are also waiting to be handed out at the conclusion of Road Atlanta’s 10-hour season finale.

With all the complexities of the TPNAEC and its multiple points payouts during the race in mind, we’ll focus on the primary titles.

Prototype

The long-held lead by Action Express Racing’s Felipe Nasr and Eric Curran in the No. 31 Cadillac DPi-V.R has come under fire from CORE autosport’s Pro-Am ORECA 07-Gibson piloted by team owner Jon Bennett and co-driver Colin Braun.

Take the modest four-point advantage AXR holds over CORE (254-250), and the sizable gap to the third-place Wayne Taylor Racing Cadillac team (235), and it means Petit will be a showdown between the Nos. 31 and 54 as all other drivers and teams have been ruled out of the title fight.

If CORE intends to overtake AXR in the standings, a bit of separation will be required at the checkered flag. A win by CORE won’t be enough; AXR’s No. 31 would need to finish third (285-284) or worse for the independent squad to knock off the entire field of factory DPis for the Drivers’ and Teams’ championships. If CORE places second, it needs AXR to place no higher than fourth (282-282) to emerge victorious (with more wins, CORE takes the title on a tie).

Due to IMSA’s miserly point payout structure, after second place, a similar cadence develops where a third for CORE will only bring the titles if AXR is fifth (280-280). If CORE’s fourth, AXR must be no better than seventh (278-278) for Bennett and Braun to win, and so on.

In a very general sense, if AXR is going to retain its lead and become champions for the fourth time in five IMSA seasons, the No. 31 must finish in front of the No. 54 or stay within one or two positions if both cars are running toward the front of the Prototype field.

As the Drivers’ and Teams’ points are identical, both championships will go to AXR or CORE.

On the Manufacturers’ front, Cadillac will win the title by taking the start.

GT Le Mans

Following the Prototype theme with AXR and CORE, GTLM has come down to two entries vying for the Drivers’ and Teams’ title as the rest of the grid was ruled out after Monterey.

It’s the No. 3 Corvette Racing C7.R driven by Antonio Garcia and Jan Magnussen against the No. 67 Ford Chip Ganassi Racing GT with Ryan Briscoe and Richard Westbrook. Corvette vs. Ford…it’s as ‘Murrican as IMSA can muster.

GTLM is also the only class where a significant gap is held between first and second place (299-290), and while nine points might not look like much, it leaves the Ford gang with few options to overcome the Corvette camp. In a class with nine entries, all the No. 3 team needs to do is finish fourth or better and the No. 67 is powerless to overcome Garcia and Magnussen.

Briscoe and Westbrook have two very simple choices on Saturday if they want to head home as champions: win or finish second and hope the No. 3 has a bad day. For Ford to celebrate, it will need the No. 67 to place first and watch as the No. 3 rises no higher than fifth (325-325) to take the title on a tie-breaker due to having more wins.

If the Ford is second, Briscoe and Westbrook will need the Corvette to fall out early and place eighth (322-322) or ninth (322-321) in the nine-car class to celebrate. With the C7.R’s renowned reliability, the steady driver rotation, and the fast hands among its pit crew, it would take a shocking event for the No. 3 to fall out of contention and hand the No. 67 the title if the Ford does not win the race.

FCGR’s mindset must be win-or-bust owing to the long odds involved with placing second.

As the Drivers’ and Teams’ points are identical, both championships will go to Corvette or Ford.

On the Manufacturers’ front, Ford will win the title by taking the start.

GT Daytona

Between the four-point Prototype lead held by AXR and the nine-point advantage held by Corvette in GTLM, we have Paul Miller Racing and the six points it holds over Meyer Shank Racing (303-297) resting somewhere in the middle.

PMR’s Bryan Sellers and Madison Snow have been nothing but steady in their No. 48 Lamborghini Huracan GT3, and in one of the season’s great storylines, Katherine Legge — only scheduled for the four TPNAEC rounds — has held onto second with the No. 86 MSR Acura NSX GT3 after getting the full-time nod.

Thanks to a revolving cast of co-drivers, it’s Legge against Sellers and Snow, and with a six-point gap, she has a few more options to catch and pass the No. 48 crew. But it won’t be easy.

The PMR team will be IMSA’s new GTD champions if the No. 48 finishes first, second, or third. Period. The title can tilt in favor of Legge and MSR if the No. 86 wins and the No. 48 is no better than fourth (332-331). If both teams fail to win and end up tied on points, the championship would go to the No. 86 based on having more seconds (3-1).

If Legge is second, she’d win if the No. 48 is no higher than fifth (329-329). If she’s third and the PMR drivers are no better than seventh, she’d also win (327-327). With 14 cars entered in GTD, Legge’s odds improve if the Lamborghini team struggles, but it’s also worth noting the No. 48’s worst finish this year is a sixth.

There’s no guarantee the streak will continue, but history does indicate PMR tends to get to the checkered flag, and in a competitive manner. As much as MSR would welcome bad luck visiting its title rivals, it knows defeating PMR will likely have to take place over 300-plus hard-fought laps.

As the Drivers’ and Teams’ points are identical, both championships will go to PMR or MSR.

On the Manufacturers’ front, Lamborghini will win the title if a Huracan GT3 finishes seventh or better. Acura’s only shot will come by winning and having the top Lamborghini place eighth or worse.