CARMEL, Ind. — Crunching the FedEx Cup numbers has never been Jordan Spieth’s thing. Well, it’s not really anyone’s thing, as the various permutations can cause a headache.

But Spieth is versed enough in the subject to know that a good day on Sunday can vault him into the top 5 in the FedEx Cup standings heading to the Tour Championship in Atlanta.

And from that position, a win in the season-ending event means an overall FedEx Cup title.

Spieth, who is tied for ninth and 10 shots back of tournament leader Dustin Johnson through three rounds of the BMW Championship, let two late bogeys at Crooked Stick Golf Club ruin what was an otherwise solid day.

And those bogeys knocked him out of the top five in the FedEx Cup projections for the moment.

“I couldn’t tell you in the last four years at any point in time how many points I’ve had,” said Spieth, who won the FedEx Cup title last year after capturing the Tour Championship. “I don’t think about that much. If I get up in the top 10 (at the BMW), maybe I can be in the top 5 (in the FedEx Cup standings). At this point, that’s the goal.

“You want to be in the top 5 going to Atlanta. I don’t know what it takes, but I know if I’m in the top 10, I should stay sixth (where he began the week). And if I win in Atlanta, it would be hard not to win the FedEx Cup.”

But not guaranteed, which is why getting in the top 5 is so important.

Spieth’s closing bogeys Saturday, after playing the first 16 holes in 6 under par, knocked him to a projected seventh position in the FedEx Cup standings. So much can alter that on Sunday, including those players around him in the points standings and what they do in the tournament.

Tournament leader Johnson is projected to go to No. 1 with a victory here, with Patrick Reed second, Jason Day third, Adam Scott fourth and Paul Casey fifth. If that holds, any of those players would win the FedEx Cup with a victory at East Lake.

Spieth is not a fan of the system that allows the FedEx Cup champion to be crowned by winning at East Lake while not having necessarily the best season on the PGA Tour.

It would be hard to argue with Johnson, Day or Scott capturing the title. All have multiple victories this year. But Reed and Rory McIlroy, who is sixth in the projected standings, have just one apiece. Spieth has two.

The FedEx Cup points system gives four times more points during the playoff events than a regular season event. And the points reset after this week, so that all 30 players who make it to Atlanta have a mathematical chance to win the overall title.

“I don’t have the answers to how to do it,” Spieth said. “It just seems odd that someone can dominate for a year and not win a significant bonus. In order to achieve what they call a yearlong race, more adjustments can be made. But I’m happy with the way it worked out last year.

“If it weren’t myself or Jason last year (both won five times on the PGA Tour), it would have been something to look at. I think they might have taken a closer look at changing again. Hopefully I can do it again, and maybe they don’t look at it again.”

Sunday’s final round could also have an influence in other areas.

J.B. Holmes (third at the BMW Championship) and Matt Kuchar (tied for fifth) are hoping to get Ryder Cup at-large picks from U.S. captain Davis Love III. So is Bubba Watson, who is tied for 17th.

Rickie Fowler, also in need of a pick, is having a tough week. He is tied for 59th and is projected to finish 30th in the FedEx Cup, needing to be among the top 30 to advance to Atlanta.