Louis Oosthuizen takes early lead at Open Championship

South Africa's Louis Oosthuizen posted a bogey-free, 6-under-par 64 to grab the early lead during the first round of the Open Championship at Royal St. George's in Sandwich, Kent, England.

Oosthuizen held a one-stroke lead over Brian Harman and Jordan Spieth.

The trio of Harman, Canadian Mackenzie Hughes and South African Dylan Frittelli, grouped together for the first two rounds, all went low. Harman birdied No. 18 to tie Spieth at 5-under 65 and Hughes and Frittelli each shot 4-under 66. Stewart Cink, 48, was also 4-under with one hole to play.

Oosthuizen landed his tee shot on the par-3 16th inside eight feet of the pin to set up his sixth birdie of the day. After warming up with seven pars to start his round, he had a three-birdie run on Nos. 8-10 and later tied Spieth at 5 under with birdies on Nos. 13 and 14.

Following an early bogey, Spieth's long putt from the fringe on No. 5 kicked off a string of four straight birdies as he staked out his spot near the top of the leaderboard. He added two more birdies on the back nine as he jockeyed for position with Oosthuizen.

Oosthuizen's only major victory came at the 2010 Open, but he has six runner-up finishes in majors -- including this year's PGA Championship and U.S. Open.

The 2017 Open champion, Spieth entered the week leading all players in Open Championship scoring average since 2015 (69.6), according to the PGA Tour. His 65 marked his 13th Open round in the 60s in that span, which leads the pack as well.

Harman was the first player to touch 5-under, compiling five birdies in his first eight holes before dropping a shot on the ninth. There was a two-shot swing when Hughes sank his fifth birdie on the par-4 12th while Harman bogeyed the hole, suddenly delivering the Canadian a brief two-shot lead.

That was until Spieth and Oosthuizen surged ahead.

Englishmen Andy Sullivan, Jack Senior and Danny Willett as well as South African Justin Harding shot 3-under 67. Norway's Viktor Hovland and England's Paul Casey each shot 68 to join a group at 2 under. Four-time major winner Brooks Koepka opened with a 1-under 69.

Bryson DeChambeau only hit one fairway in regulation over his first 12 holes, but his scrambling kept him afloat. No. 12 was the start of a stretch of three birdies for him; he hit iron off the tee at the par-5 14th to ensure he found the fairway, still managed to reach the green in two and two-putted. He finished with a 1-over 71.

Defending champion Shane Lowry and world No. 2 Jon Rahm, Oosthuizen's playing partners, shot 1-over 71.

World No. 1 Dustin Johnson stood at 2-under with a few holes to go. Northern Ireland's Rory McIlroy, Phil Mickelson, Justin Thomas and Rickie Fowler were among the stars scheduled to tee off late in the day.