Milwaukee, WI -- (Sports Network) - Richard S. Johnson closed with a six-under 64 Sunday to earn his first PGA Tour win at the U.S. Bank Championship in Milwaukee.

Johnson completed the event at 16-under-par 264.

"It's just amazing. You're thinking about it all the time of course when your leading, but it's hard. You try to block the thought, but it keeps popping up there," said Johnson, who collected $720,000 for the win. "It's unbelievable. I've worked very hard this year."

Ken Duke finished second at minus-15 after closing with a five-under 65 at Brown Deer Park Golf Course.

Dean Wilson and Chad Campbell both closed with rounds of 65 for a share of third place at 13-under-par 267. They were joined by former U.S. Ryder Cupper Chris Riley, who carded a 66 in the final round.

Joe Ogilvie, the 2007 winner, shared sixth place with Kenny Perry and three others. Ogilvie shot 67 on Sunday, while Perry fired a 64 to post 12-under-par 268.

"I didn't really look at the leaderboard until I holed my nine-iron for eagle on 15," stated Perry, who won his last two starts and three of his last five overall. "I hit some real close iron shots coming in and I shoot 30 on the back nine. I never thought about winning this week, I was so far behind. Then the magic showed up for nine holes."

Johnson was not a factor on the front nine as he carded two birdies and two bogeys through six holes. Birdies on the seventh and 10th got him into contention at 12-under.

Duke birdied the fourth and sixth to join Campbell and Troy Matteson in the lead at 12-under. He ran home a 17-foot birdie effort on the 10th to move to 13-under.

Johnson followed his birdie on 10 with another on 11 to join Duke at 13- under. He parred the next three and was joined atop the leaderboard by Ogilvie and Campbell.

Duke fell one back with a bogey on the 14th after missing the green with his tee shot at the par-three. He ran home a 17-footer for birdie to get back to 13-under.

Johnson two-putted for birdie No. 15 to remain one ahead of Duke and that's where it became a two-man show.

Duke birdied the 16th from nine feet out to move to 14-under and into a share of the lead. Johnson answered with a 16-foot birdie putt on 17.

At the last, Duke knocked his second to the par-five closing hole into a greenside bunker. Johnson's second stopped 17 feet from the hole. Duke knocked his bunker shot to four feet.

Johnson watched that and then rolled his eagle effort to within two feet of the hole. Duke drained his birdie putt to tie for the lead, but Johnson responded by kicking in his birdie try for the win.

"You've got to take it with a grain of salt," Duke said. "Richard played great. I shoot five-under on Sunday and I don't get it done. There is nothing you can say about that."

After shooting 70 on Saturday, Johnson became the first player since Scott Hoch in 1997 to not card four rounds in the 60s and win this title.

"Yeah it did a little bit," Johnson said when asked if it felt like match play. "He was quite a ways in front there, then I birdied six and seven and got back to him on the back nine. I played really solid and Ken played terrific too. I was a neat game."

Perry and Ogilvie were joined in sixth place at 12-under-par 268 by Troy Matteson (66), Patrick Sheehan (67) and George McNeill (68).