US PGA champion Justin Thomas moved into pole position to win the FedEx Cup title and $10million bonus after claiming a share of the halfway lead in the Tour Championship.
Any of the 30 players in the season-ending event can theoretically win the massive pay day, but only the top five in the standings are assured of doing so by claiming the $1.53mn first prize in Atlanta.
Open champion Jordan Spieth began the week with a 200-point lead over Thomas, with world number one Dustin Johnson, Marc Leishman and Jon Rahm the other players in control of their own destiny.
But while Spieth could only manage a second round of 70 at East Lake to remain three under par, playing partner Thomas eagled the 18th in a 66 to share top spot on seven under with England's Paul Casey and Webb Simpson.
"It's nice to have everything in my own hands," said Thomas, who has already won five times this season, including a maiden major title at Quail Hollow.
"I felt like I was leaving a lot of shots out there. I was hitting some really good putts that weren't going in and it's easy to get frustrated, but I just tried to stay patient and calm and I was glad to be rewarded by that (eagle) on 18.
Finishing in style.
— PGA TOUR (@PGATOUR) September 22, 2017
An 18th-hole EAGLE catapults @JustinThomas34 into a tie for the lead! pic.twitter.com/5zoNBqOvMA
"I'm just trying to play the best I can and win a tournament. It's not like I'm trying to win the Tour Championship and the FedEx Cup, that just comes with it.
"All I'm trying to do is pick apart the golf course and pick my spots and if I drove it like I did yesterday and for some of the holes today, you can really make a lot of birdies out here. Hopefully the putter can heat up and we can see if we can have some fun this weekend."
Simpson held a three-shot lead after five birdies in his first 11 holes, only to double bogey the 13th after hitting a tree with his attempted recovery shot following a wayward drive.
The former US Open champion still recorded a 67 which was matched by Casey, who has a record 15 top-five finishes in the last three years on the PGA Tour without recording a victory.
🔥The rookie is heating up🔥#QuickHits pic.twitter.com/vT3KbY9B63
— PGA TOUR (@PGATOUR) September 22, 2017
"I've had a very good season to this point but I'd like to turn mine into a great one and the way to do that would be with a victory this week," Casey told Sky Sports.
Olympic champion Justin Rose, who has twice been a runner-up at East Lake, was a shot off the lead alongside Rahm, Patrick Reed and Gary Woodland.
"This would be a great tournament to win," Rose said. "It's one of those other tournaments that separate themselves from regular events.
"You've go the best of the best here and as we've seen, guys who win this often do very well in the FedEx Cup and you're holding two trophies at the end of the week.
"I've got to focus just on this tournament and if the FedEx Cup goes my way then great, but some other guys have a say in that one. I need Jordan and Justin to finish outside the top three I think, but coming in number eight gave me a realistic chance."
