American John Daly, meanwhile, had another day hed prefer to forget on his frustrating Australian visit, shooting a 78 in a round that culminated with him smashing a spectators camera against a tree.
After pushing his tee shot wide on the ninth hole ' his last ' Daly walked to a clump of trees, where spectator Brad Clegg tried to take a picture at close range.
Daly reportedly snatched the camera and smashed it against the nearest tree, telling the man, You want it back, Ill buy you a new one.
He later released a statement via tournament organizers.
I was looking to take a drop and a camera was six inches away from my face. If I was 10 under, I would have felt the same, Daly said in the statement. My eyes are still burning from the flash of the camera.
Daly, who missed the cut at both the Australian Masters and the Australian PGA in the last two weeks, is being paid an appearance fee for his three-tournament trip Down Under. He had three double bogeys, three bogeys and four birdies Thursday at Royal Sydney Golf Club and looks unlikely to make the cut.
Dartnall was unaware of the Daly drama as he pulled together six birdies and an eagle, offset by a lone bogey.
A second-year pro, he shot a 10-under 62 in a qualifying round on Monday.
It is one of the bigger tournaments and there is more attention on it, but it does not really change how I think, he said. Maybe it will later on. At the moment I feel pretty calm.
Goggin is also on a streak, having finished second to Geoff Ogilvy in the Australian PGA at Coolum last Sunday.
He got off to a sizzling start, with six birdies in his first eight holes and capped the round by hammering a 4-wood from more than 274 yards to tap-in range for an eagle at the 585-yard 16th.
He bogeyed the difficult par-3 17th, then recovered by sliding home a 7-foot putt for birdie at on No. 18.
I feel like I believe in myself a lot more, Goggin said.
Porter, who joined the leaders with birdies on three of his last four holes shortly before darkness fell, was delighted with his performance.
This is a total surprise. Ive been up and down the whole year, but the last six months has been miserable, he said.
New Zealanders Mark Brown and David Smail and Australian Rod Pampling were tied for fourth, two strokes off the pace. Australian John Senden, who won the Open when it was last at Royal Sydney in 2006, shot a 68, while former champion Peter Lonard was in a group of seven players who shot 69.
Robert Allenby had a 71 and pre-tournament favorite Ogilvy a 72.
Daly is making his first visit to Australia since 2002, when he left in controversial circumstances.
After taking a triple-bogey on his last hole at the Australian PGA at Coolum that year, Daly threw his putter and ball into a greenside pond and later failed to sign his scorecard, disqualifying himself.