AKRON (United States) • Jordan Spieth's bid to dethrone Rory McIlroy as golf's world No. 1 got off to a slow start on Thursday at the WGC-Bridgestone Invitational after a lacklustre opening round left him five shots off the pace.
The reigning Masters and US Open champion will supplant injured Northern Irishman McIlroy at the top of the rankings this weekend if he wins the US$9.25 million (S$12.8 million) event at Firestone Country Club.
However, the 22-year-old's push for top spot faltered with a patchy level-par 70 that saw him finish the day well down the leaderboard that was headed by New Zealand's Danny Lee.
Spieth, who has not played since the British Open at St Andrews last month, blamed ring-rustiness after a round containing two birdies and two bogeys. But he is confident he can take on the leaders.
"The challenge is just getting into it," the American said. "I just felt like I started the round today with little to no emotion. It's a battle but it's one that I'm looking forward to because I'm not out of it."
Spieth is using the tournament as preparation for next week's PGA Championship at Whistling Straits in Wisconsin, where he will be chasing his third Major of the season.
South Korea-born leader Lee took sole possession of the lead after sinking a succession of long putts to shoot 65.
Teeing off on the back nine, he opened with a pair of birdies on the 10th and 11th.
He dropped a shot on the 12th with a bogey after his tee shot found the left greenside bunker.
However, the New Zealander came roaring back on the 13th, draining a 47-foot putt to move back to two under after four holes.
A bogey on the par-three 15th was offset by a further birdie on the 16th.
Three more birdies at the start of the front nine, including a 29-foot putt on the par-five second and a 28-footer on the fourth, took him to five under.
"It was a good day for me," said Lee. "I left a couple of short birdie putts out there. It may sound a little bit too greedy but I did. And I was hitting it that good, and I was very happy with my result."
One off Lee's pace were American veteran Jim Furyk and Northern Ireland's Graeme McDowell, who both carded 66s.
Newly-minted British Open champion Zach Johnson was back with Spieth in a group of 15 players at level par.
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