On a day when Jordan Spieth finished five strokes off the pace, the 25-year-old Lee, who won his first PGA Tour title in a playoff for the Greenbrier Classic last month, fired a five-under-par 65 at Firestone. He ended a challenging day one ahead of American Jim Furyk and Northern Ireland's Graeme McDowell.

Texan Spieth birdied his final hole for a 70 in the third of four World Golf Championships (WGC) events to be held this year.

"Making birdie to shoot even (par) feels better than making bogey to shoot one-under," Masters and U.S. Open champion Spieth told reporters after his first competitive round since his tie for fourth at last month's British Open.

"That's just the way it works. It was a nice finish. I hit three really good shots. Feels good to take that momentum and see one kind of fall in the lip," he said of his seven-foot birdie putt at the par-four 18th.

"I had quite a few (putts) that looked pretty good today that just didn't quite go. As far as my first round back after a couple-week layover, I'm pleased with the way we finished."

While Spieth, arguably the greatest putter in the game, was not quite at his best on the firm Firestone greens, Lee celebrated "a good day" as he accrued seven birdies and two bogeys to take the outright lead.

"I was hitting it that good, and I was very happy with my result," said Lee, 25, who was born in South Korea but is a citizen of New Zealand where he spent his youth.

"The course out there is in such phenomenal conditions. It's very firm, greens rock hard. If you can just hit the fairways, you're getting a lot of short irons (into the greens).

"It was a good day for me, even though I left a couple short birdie putts out there. It's tough for everybody, but I like it though."

Veteran Furyk, a 17-times winner on the PGA Tour, was also at five under with one hole to play but bogeyed the par-four last after being unable to get up and down from behind a tree in the right rough, 38 yards short of the green.

Several players in the elite field of 77 struggled in the firm conditions. Five-times major champion Phil Mickelson carded 76 and fellow American Troy Merritt ballooned to an 82 just four days after winning the Quicken Loans National.

Latest News from Sports News Desk