US Open champion Rory McIlroy shares top spot with four others at the halfway mark of the Korea Open.
The world number three is tied for the lead with American Rickie Fowler, defending champion YE Yang, Korean Mo Joong-kyung (66) and Australian Bronson La'Cassie (67) at five-under.
McIlroy, 21, reached six-under after 12 holes but was patchy on the back nine with both birdies and bogeys.
McIlroy, who finished second at last week's Alfred Dunhill Links Championship, is chasing his first win since his US Open triumph.
"It was a good round. I felt it could have been lower, but I played solid golf and holed some nice putts," said McIlroy, who finished third in 2009.
"It's a good start to the tournament and I have put myself in a good position going into the weekend."
Overnight leaders Yang and Fowler both had rounds of one-under 70s to remain tied for the lead while Mo struck some luck when he eagled the par four 15th from his approach shot.
World number 36 Fowler, the 2010 US PGA Tour Rookie of the Year, is firmly in the hunt to claim a first career title after making his Ryder Cup debut last year.
"I got it around and I am in a good position for the weekend, so that's a positive. I didn't hit it as well as the first round and I struggled with the speed of my putting over the last few holes, so I have some improving to do. But I am still in a good position for the weekend," said the 22-year-old.
"It is a tough golf course and there are a lot of good players at the top of the leaderboard. I think the key for the weekend is driving the ball well, and if I do that, I think everything else will fall into place."
Korean Kim Meen-Whee is three shots behind the leaders on two-under after his second round of 71.
His compatriots Hong Soon-sang, Noh Seung-yul and amateur Lee Soo-min are tied for seventh a shot further back.