-10 J Rose (Eng) -6 C Pettersson (Swe), C Wi (Kor) -5 J Overton (US) -4 R Moore (US), J Day (Aus) Selected others: -2 V Singh (Fij) +3 T Woods (US)
Rose blew a three-shot lead at last week's Travelers Championship
Justin Rose opened up a four-shot lead after the third round of the AT&T National in Pennsylvania.
The Englishman, who squandered a three-stroke final-round lead at last week's Travelers Championships, fired a 67 for a 10-under total of 200.
Sweden's Carl Pettersson shot a round-of-the-day 65 and South Korean Charlie Wi went around in 70 to tie for second.
Tiger Woods recovered from bogeys on his first two holes to hit his second successive 70 to lie 13 off the pace.
"I really enjoyed the round. When I was in trouble, my short game really pulled me through," said Rose.
"There were a couple of times on the back nine I kept the momentum going. I thought the key moment of the day actually was a bogey I made on 14. I probably hit the wrong club there and I was in a wicked lie.
"I tried to actually play safe to get it on the green, couldn't even hit the green and then got an even worse lie, managed to chop it to four feet and made the putt.
"That was probably the only little bit of emotion I showed all day with a fist pump, but it was for bogey. It was a good day.
"I really enjoyed the golf course again, and I think that's going to be my mindset - just to keep enjoying this place."
Rose, whose second-round 64 had given him a one-shot overnight lead, will be hoping to avoid a repeat of his last-day jitters at the Travelers in Connecticut.
The 29-year-old had three bogeys and one double bogey on his back nine there to eventually finish three strokes off a play-off, which was eventually won by Bubba Watson.
Rose will be aiming to pick up his second PGA Tour title after breaking his US duck with victory at the Memorial earlier this month.
And he insisted that the disappointment of Connecticut will not play on his mind.
"I think what I'm doing well, which is what's putting me in this position, is I'm not carrying any baggage over from one week to the next," said Rose.
"I didn't go into Hartford last week thinking 'you just won, keep it going' and I didn't come into this week thinking 'you've just blown a win.'
"I'm just coming into each week seeing it as a new challenge and starting from hole one of the tournament. Although I'm on a great run, I'm not carrying that run with me mentally week to week."
Woods, meanwhile, has been struggling to find his form since returning to competitive action following revelations about his private life at the end of 2009.
And the 34-year-old did well to avoid an embarrassing score after countering bogeys - at one, two, six and 15 - with four birdies.