Ranking the 2015 FedEx Cup Contenders at Midsummer Mark

Predicting who will win the FedEx Cup is tricky business. 

Thanks to points reshuffles, a complex scoring system and increased point totals during the playoffs, the FedEx Cup is (by design) a wide-open race until the Tour Championship, where every player in the 30-man field theoretically ought to have a chance to win the Cup.

An example: Few predicted Billy Horschel, who had done little all year, would win two playoff events to take the title. 

Thus, don't count out players such as Patrick Reed (9), Justin Rose (15), Hideki Matsuyama (16), Brooks Koepka (17), Rickie Fowler (24) and others. 

So, how do we rate the contenders? We take a look at the strength of recent play and past performances at the big tournaments left on the docket after this week: the WGC-Bridgestone Invitational, the PGA Championship, which was played at Whistling Straits in 2010, and the FedEx Cup playoff events.

The Barclays is being contested at a new venue this year, so past performance is no help, but the BMW Championship was held at Conway Farms in 2013, so we can look to performance there. The Deutsche Bank Championship and the Tour Championship are both at their traditional venues, of course. 

With that said, click through for the rundown. 

7. Jimmy Walker

LM Otero/Associated Press

• Points/position: 1,951/3
• Events: 19
• Wins: 2
• Top-10s: 6

Jimmy Walker's recent form includes a tie for 30th at the Open Championship and a tie for 58th at the U.S. Open, so he hasn't exactly been lighting it up. 

Still, Walker is a big-time player who leads the tour in strokes gained in putting and is fifth in total strokes gained.

Walker tied for 26th at the WGC-Bridgestone Invitational last year, so there are no indications he's on the verge of winning in Akron between that fact and his recent play. Likewise, he missed the cut at Whistling Straits in 2010, so a PGA Championship victory seems unlikely as well. 

Assuming the above, Walker will most likely need a win and strong showings in the other three playoff events to win the FedEx Cup.  

6. Rory McIlroy

Charlie Riedel/Associated Press

• Points/position: 1,510/8
• Events: 8
• Wins: 2
• Top-10s: 6

While Rory McIlroy may be the most objectively talented golfer on this list, the concern is how—and when—he will return from injury. 

We'll assume Rors returns for the PGA Championship and that he plays well at Whistling Straits (where he tied for third in 2010).  

McIlroy finished inside the top 10 in three of the four playoff events last year. He tied for eighth at Conway Farms in 2013 and won the Deutsche Bank Championship at TPC Boston in 2012. Thus, if he's able to get his game in order upon his return, he'll be heading to a track of courses at which he's played well. 

5. Dustin Johnson

Andrew Redington/Getty Images

• Points/position: 1,607/5
• Events: 15
• Wins: 1
• Top-10s: 7 

After looking like the British Open was his through two days, Dustin Johnson limped in with a pair of weekend 75s. He tied for second—and should have won—the U.S. Open prior to that. He has seven top-10 finishes in 15 starts this season, so his form has been consistently solid. 

Looking ahead to the PGA Championship, Johnson tied for fifth at Whistling Straits in 2010, so he's displayed aptitude at the Wisconsin track. 

He's also been a solid playoff performer, notching top 10s in all four events in 2012, although he didn't play well at Conway Farms in 2013. He's won two playoff events—they were contested at different courses than this year's venue—and has a good track record at East Lake. 

Thus, the odds of D.J. winning again this season and at least playing well at the season's final major are high. 

The tour's leader in driving distance, Johnson is eighth in total strokes gained and third in scoring average. 

4. Bubba Watson

David J. Phillip/Associated Press

• Points/position: 2,043/2
• Events: 13
• Wins: 2
• Top-10s: 6

Bubba Watson rebounded from a missed cut at the British Open (where he never plays well) with a second-place finish at the RBC Canadian Open. He won and tied for 13th in his two starts prior to the season's third major. 

Watson finished second the at the 2010 PGA Championship at Whistling Straits, so he has to be a "horse for the course" at this year's edition.

He's only cracked the top 10 once in Akron, but he has recently tended to step up his game in WGC events. 

In recent years, Watson has had no problem racking up top-25 finishes in FedEx Cup playoff events. So far he hasn't threatened, however, so a playoff win seems unlikely. Still, a win at the PGA Championship and a solid run in the playoffs could earn him the Cup. 

Watson is second on tour in total strokes gained and second in scoring average. 

3. Zach Johnson

GLYN KIRK/Getty Images

• Points/position: 1,522/7
• Events: 19
• Wins: 1
• Top-10s: 8 

Zach Johnson triumphed in dramatic fashion at the Open Championship. Prior to that, Johnson tied for third at the John Deere Classic and finished sixth at the Travelers Championship. 

He has two top 10s at the WGC-Bridgestone Invitational in the past four years, so the Iowa native looks primed for a strong showing at the Akron course. Also, Z.J. tied for third at the PGA Championship at Whistling Straits in 2010, which suggests he'll play well there this year. 

Looking to the playoffs: Johnson won the BMW PGA Championship in 2013, the last time it was contested at Conway Farms.

Impressive recent form and a strong record at upcoming venues suggest Johnson is in prime position to take home the FedEx Cup.  

2. Jason Day

Minas Panagiotakis/Getty Images

• Points/position: 1,793/4
• Events: 14
• Wins: 2
• Top-10s: 7

Jason Day won the RBC Canadian Open in his most recent start and narrowly missed at St. Andrews. In other words, he's in form. 

He tied for fourth at the WGC-Bridgestone Invitational in 2011, so he clearly has aptitude at the Akron track and is among the favorites for the PGA Championship at Whistling Straits. 

Day tied for fourth at Conway Farms in 2013, so a strong showing at the BMW Championship seems likely. Last year, he finished inside the top 10 in three of the four playoff events. With his recent surge, it's not unlikely that he'll be similarly strong this year. 

These stats confirm the Australian is one of the best on tour: Ninth in total strokes gained, first in birdie average and 11th in scoring average. 

1. Jordan Spieth

Jon Super/Associated Press

• Points/position: 3,763/1
• Events: 19
• Wins: 4
• Top-10s: 12

T3, 1, 1, T4 are Jordan Spieth's first last four starts. In other words, he's playing brilliant golf right now. Looking ahead, Spieth will likely play the WGC-Bridgestone Invitational, the PGA Championship and the four FedEx Cup Playoff events. 

While he hasn't had any real success in Akron, he has to be considered a favorite at Whistling Straits for the PGA Championship.

Projecting for the FedEx Cup playoffs, Spieth tied for 16th the last time the BMW Championship was contested at Conway Farms. He also tied for second in 2013 at East Lake, the site of the Tour Championship. 

The tour leader in total strokes gained, second in birdie average and first in scoring average, Spieth has a sizable lead in the FedEx Cup points standing and has to be the favorite to win the season-long points race. 

All stats via PGATour.com