Former world number one Rory McIlroy, making his competitive return after a four-week break, was handily placed three shots off the pace after producing a late flourish in the opening round of the Korea Open on Thursday.
The 24-year-old Northern Irishman, who has slipped to sixth in the rankings after a turbulent year both on and off the course, carded a one-under 70 at the OneAsia Tour event as he continued his search for an elusive first victory of the year.
Japan tour regular Jang Ik-jae returned an error-free 67 to take the lead at Woo Jeong Hills Country Club near Cheonan, south of Seoul.
Twice major winner McIlroy dropped a shot at the third before rallying with a birdie at the next hole. He then made a double-bogey at the par-three 13th after finding water.
"I wasn't very comfortable with the tee shot," he told reporters. "I took a long time to get settled over it and then just didn't make a very good swing.
"Some of the pin positions out there today were brutal, just cut on slopes and very hard to get close to them, and when you did get close you left yourself very tricky putts."
McIlroy ended his round in style with birdies at the 14th, 17th and 18th.
"I felt I was a little rusty after the four weeks off but I battled back nicely and to end up under-par for the day wasn't too bad," he said.