Breaking down FedEx Cup scenarios

ATLANTA -- The seven-year streak which has seen the Tour Championship winner also claim the FedEx Cup and the $10 million bonus is in serious peril with one day remaining in the season-ending PGA Tour event at East Lake.

None of the top five players -- Jordan Spieth, Justin Thomas, Dustin Johnson, Marc Leishman or Jon Rahm -- are closer than 5 strokes to tournament leader Paul Casey heading into the final round of the 30-player tournament.

That means all manner of scenarios exist going into the final day. The last time the Tour Championship winner did not claim the FedEx Cup title was in 2009 when Phil Mickelson won the tournament and Tiger Woods claimed the overall trophy.

Here is quick look at some of the possibilities.

Casey. The third-round leader had a 4-stroke lead at one point and has been under par every day. At 10th in the FedEx standings, he would need to win and have Spieth finish in a three-way tie for fourth or worse, along with other scenarios. If it ended Saturday, Casey would be the FedEx Cup champ.

Kevin Kisner. The Georgia Bulldog didn't seem too stressed about the big prize, bolting East Lake after a 64 to catch the football game against Mississippi State in Athens, Georgia. At 18th in the standings, he would need a lot to happen -- including rally from 2 back of Casey. But a win would be the biggest of his career.

Xander Schauffele. The PGA Tour rookie who won at the Greenbrier is making the most of his first trip to the Tour Championship, shooting 65 on Saturday. He would need Spieth to finish worse than 23rd to win the FedEx Cup, so Schauffele's sole goal is to hoist the tournament trophy.

Brooks Koepka. The U.S. Open champion shot 68 despite two closing bogeys. At ninth in the FedEx standings, he would be the overall champion if he can rally to win and Spieth, Thomas and Johnson all stay outside of the top two or three -- which is the case now.

Patrick Reed. At 23rd in FedEx Cup points, the overall title appears out of reach, but Reed is in search of a victory this year. Like Casey, he could become the first player since Bill Haas in 2011 to make the Tour Championship his only win of the season.

Thomas. He failed to pounce Saturday, shooting even par after holding a share of the 36-hole lead to fall 5 back of Casey. Thomas is tied for fourth and projected to finish second in the standings but could claim the overall title if he finishes in the top three or better if Casey does not win.

Jason Day. Finally showing some form in recent weeks, Day is also in search of a lone victory this season. A double-bogey on the 16th hole Saturday stalled a round that saw him make four straight birdies on the front side. He's 6 strokes back with little to lose.

Rahm. The young Spaniard also didn't make a move, shooting even par to finish 6 back of Casey. If Rahm can move into a tie for second, he's got a shot at the overall title.

Johnson. He was unable to move into contention, shooting 69 to stand 8 behind Casey. DJ needs to go low and finish no worse than third if he has any hopes of claiming the FedEx Cup.

Spieth. Much like Johnson, he couldn't get anything going on Saturday, and is tied for 13th, 8 strokes back. He can still win the FedEx Cup title if he finishes somewhere in the top six, but more likely he'll need to be in the top three and finish ahead of Thomas.

Leishman. Fourth in the FedEx standings coming off his victory at the BMW Championship, Leishman seems to have left his game behind in Chicago. He has shot just one round in the 60s and is tied for 22nd. To have any chance, Leishman would need to pass about 20 players on Sunday.