"Pretty stress-free round," Dufner said.
Harrington didn't feel as though he hit the ball much worse in a round of 73. He realized it would be difficult to back up his record score on the Copperhead course with another low score, and it crept into his putting, especially on the back nine.
"I'm happy with my game, but when you shoot a good score, it's hard to match the next day," Harrington said. "When you're leading the tournament, it's hard not to be a little bit cautious, and I think at times I was on the greens."
William McGirt had a 68 and joined Harrington at 8-under 134.
Luke Donald, who can return to No. 1 in the world with a win, had a 68 and was in the large group at 7-under 135 that included Puerto Rico winner George McNeill.
Canadians Stephen Ames, David Hearn and Graham DeLaet all missed the cut.
Harrington was still leading when he hit weak putts, all of them for birdie from inside 15 feet, on three straight holes. It caught up with him on the sixth, when he marked his ball but failed to go through his routine and wound up missing a 15-inch par putt. Then, he three-putted the seventh hole and suddenly found himself two shots behind.
The good news — at least before he was picked for a drug test — was that Harrington was still in the mix.
"I didn't do too much damage today," Harrington said. "It wouldn't have been the end of the world if I didn't have those two three-putts. It could be OK. But the great thing his, having shot a good score yesterday, I felt that if I played the best golf on the weekend, I would be the winner. I'm still in good position."
Harrington figured he would either post another good score and have a chance to run away from the field, or get an ordinary score and have to work hard on the weekend. It turned out to be the latter. Twelve players were separated by four shots.
Dufner thought he would need another good round to get into contention. Being in the lead was a bonus.
"You have to do a little bit of chasing, and you're kind of hoping in the back of your mind he comes back to you a little bit," Dufner said. "I don't know why that's so hard. I've dealt with it; every player has dealt with it. You shoot a great number and you feel like you're going to shoot under par every day, and you kind of back up the next day. That seems to be like a law of averages thing."
Dufner just did his own thing.
He handled the par 5s, making three birdies. He made birdie putts of 15 feet on the third hole and 25 feet on the ninth. And he never had to sweat over any par putts.
Dufner is 0-for-159 on the PGA Tour, and as much as he follows golf, no one had to tell him that he's the only player from the top 50 in the world ranking who has not won on any major tour. Dufner is at No. 39, and he realizes he's there for a reason. He is playing good golf, doing just about everything right except winning.
His best chance last year was at the PGA Championship, when he dropped shots down the stretch and lost in a playoff to Keegan Bradley at Atlanta Athletic Club. Dufner feels his time is coming, and he even decided to change the way he plays.
As much as he likes to keep the ball in play, an aggressive side of him wants to fire at every flag.
"It's a bit of a mind game with me," he said. "I tend to be a little too aggressive at times and get myself in trouble. After last week, I kind of thought about it. If I felt comfortable or if I had a good number, I would play aggressive. But I think when I was a little bit uncomfortable or had a bad number with a club, I would try to find the fat of the green and maybe make a par from 30 feet."
A good example of that came on the par-3 13th, with the pin front. He hit 6-iron to 30 feet for a par. A 7-iron would have worked, but missing slightly with that club might put him in the water.
As for being the lone guy in the top 50 without a win?
"It's a good thing that I've played that well to be ranked that high without a victory, because the victories really jump you up in the world rankings," he said. "It's a little disappointing that I have not won yet, but there's a lot of events this year and next year and the year after."
Jim Furyk, who won two years ago at Innisbrook, felt similar to Harrington. He was playing better than his score. He had to settle for a 70 on Friday and was in the group at 6-under 136, along with Sergio Garcia, John Senden and Kenny Perry, the only grandfather in the field at age 51.
Harrington also built some optimism for Ernie Els and Retief Goosen, both of whom are trying to qualify for the Masters. They were in the group just five shots behind. Goosen is just outside the top 50 in the world ranking, while Els would have to win at Innisbrook to get into the top 50 — and a win makes him eligible, anyway.
DIVOTS: Heath Slocum opened with a 69 and had to withdraw before the second round with what he believed to be food poisoning. ... John Daly bogeyed his last two holes for a 72, but he made the cut on the number. ... Geoff Ogilvy wore a green pants, and some in the gallery reminded him he was a day early. Padraig Harrington had a different take. "It's St. Patrick's Day in Australia," he said.Suggest a correction