WAHIAWA — Over the course of a far-flung summer of golf, Kaimuki junior Chan Kim discovered the best way to hold on to an advantage is to push it — and putt very, very well.

After opening with back-to-back 69s, Kim took a one-shot lead into yesterday's final round of the Army Invitational. He finished it off by firing a 4-under-par 68 at Leilehua Golf Course.

University of Hawai'i senior Pierre-Henri Soero came closest to catching Kim with a 67 that left him three back. Seven-time champion Brandan Kop (73—212) took third and Samuel Rodriguez III (71—213) was fourth.

Defending champion Matthew Ma (72), about to start his senior year at Oregon, and first-round leader Ryan Masuda (75), from the Big Island, shared fifth at 214.

"I knew I had to shoot under par today because I know those guys from college can go really low," Kim said. "I was thinking if I could shoot another 69 today it should be OK. It was a lot better than I expected."

The reigning state high school champion never flinched in the midst of a mob of 20-something challengers and Kop, who trailed by just one after birdieing the 10th.

Kop missed a a 6-foot birdie putt on the next hole, three-putted the 12th for bogey, then double-bogeyed the 13th after a perfect drive left him with just a 9-iron into the green.

Kop, 45, won the 1981 Western Athletic Conference title before Kim was born. He was at least 20 years older than anyone in the final group. But Kim made everyone feel old yesterday.

Rodriguez scorched the front nine in 4-under 32 to put up a threat but faded on the back. Ma and Masuda could not take advantage of Leilehua's rain-softened and receptive greens.

That left Soero, who played an almost flawless bogey-free round, and Kim, who is long and straight off the tee and showed a sophisticated knack for saving par yesterday with 27 putts.

He knocked in a pair of 12-footers for par early and made the turn in 2-under 34. He added his fourth and fifth birdies on the back and salvaged par from 7 feet on 16, 4 feet on 17 and with his wedge on 13, when he nearly holed out after sending his approach shot nearly 20 yards over the green.

"My putting and chipping have improved a lot in the last three weeks. I definitely learned a lot when I went to Junior America's Cup last week," Kim said. "I shot well there and started to feel a lot more confident about my swing and putting. I think that's what helped me today."

Kim has learned a lot all summer. He played in Michigan, Wisconsin, Washington and Utah, and leaves for Ohio today for the Westfield Championship.

He also benefited immensely from advice he received at America's Cup from King Kamehameha pro Rick Castillo, who traveled with the second-place Hawai'i team, and new Oregon coach Casey Martin, who spoke at the banquet.

"He told us the one thing that most sets us apart from the pros is the mental game," Kim said of Martin. "The pros have the ability to hit a big shot after a bad one. He just said, 'Don't play with any fear.' That really helped."

Soero, the Hawai'i qualifier at the 2005 U.S. Open, figured he needed a 65 to have any shot yesterday. He almost got there, but the way Kim was going even that wouldn't have been enough.

"Everything went OK today," said Soero, who was born in New Caledonia and graduated from a Paris high school. "Chan is a steady player and he doesn't make that many mistakes. He's pretty long too — big guy for 16 years old. He's a good player."

The Army Invitational was Kim's second open victory this year. He and Tadd Fujikawa won the HPLGA 4-Ball Championship.

Merv Matsumoto (70—222) won the Senior Flight by a shot over Wendell Kop. Michael Miguel (77—224) captured A Flight by one over Robert Nakagawa, Jim Hrysyzen (76—234) won a playoff with Lin Akiyama for B Flight honors and Neal Kido (79—245) won C Flight.

Reach Ann Miller at amiller@honoluluadvertiser.com.