Australia's Jason Day endured a roller-coaster round while American Jim Furyk was steady and consistent as they shared the lead after Saturday's third round of the PGA Barclays tournament.
Day fired a three-under par 68 that included seven birdies, two bogeys and a double bogey while Furyk shot a bogey-free 69 to leave them level for the lead on nine-under 204 after 54 holes in the first event of the US PGA's season-ending playoffs.
"It was an interesting day," Day said. "I'm really excited to get back into contention again."
Hunter Mahan was third on 205 with seven US compatriots another stroke adrift -- Cameron Tringale, Brendon Todd, Matt Kuchar, Kevin Na, Morgan Hoffmann, Kevin Chappell and Bo Van Pelt.
A field of 125 qualifiers based on points will be trimmed for next week's Boston event and then cut again for the third stop in Chicago before only 30 players advance to the Tour Championship next month in Atlanta.
Day seeks his first victory since the World Golf Championships Match Play tournament in February.
Furyk has not won a title since the 2010 Tour Championship, missing out seven times when leading or sharing the lead after 54 holes entering his next chance to snap that streak Sunday.
Furyk was a runner-up this year at the Players Championship, Quail Hollow and last month's Canadian Open, where he squandered a three-shot edge over the final 18 holes.
"I have been in this position a few times this year," Furyk said. "It's still fresh in my mind, and that will make it easier to stay patient.
"My goal is to go out, not look at the leaderboard, play my style and get my putter going hot earlier."
Furyk birdied the par-5 13th and par-4 16th to claim his spot at the top and in the odd couple last pairing with Day.
The Aussie birded the par-3 second and par-5 third, but followed a birdie at the sixth with a bogey at seven.
After starting the back-nine with a birdie, Day took a double-bogey 7 at the 13th, responded with back-to-back birdies at 15 and 16, then made bogey at the par-5 17th before closing with a birdie.
"I got off to a great start. Then the back nine began. Then the par-5s happened -- I clearly lost shots to the field there," Day said.
"I could have lost it there at 13 but I stuck it out and I played good golf after that."
Keeping his cool kept Day in the hunt.
"When you get out of sync it's hard to get back into sync," he said. "One of the things you can't do out here is react and I did a good job of staying with my swing."
- McIlroy five shots back -
Northern Ireland's Rory McIlroy, seeking his fourth win in a row on a streak that includes the British Open and PGA Championship, fired a 70 to stand on 209, five strokes off the pace.
Among his supporters this week in the crowd was Scotsman Andy Murray, the former Wimbledon and US Open champion set to contend when the year's last Grand Slam tennis event starts Monday in nearby New York.
"These guys are playing a different game out there," Murray said. "You don't realize it until you see it."
US star Phil Mickelson fired a 75 and missed the secondary cut to the low 70, but not without putting a tee shot at the drivable par-4 15th hole into a hospitality area for the second day in a row.
Mickelson's tee shot at the 289-yard hole sailed left and, as it had done Friday, landed on artificial turf outside a hospitality tent, forcing the left-hander to trudge through the crowd and make them move while he lined up his approach from the oddest of places.
He blasted over the green Friday and made bogey on his way to a round of 72. On Saturday, Mickelson found the green and two-putted for par.