July 16 (UPI) -- Louis Oosthuizen of South Africa set a 36-hole record at the British Open to grab a two-stroke lead after Friday's second round at Royal St. George's in England.
Oosthuizen separated himself from the field with two birdies and an eagle over a three-hole stretch on the back nine. He then shrugged off his first bogey of the tournament for a 5-under 65 and a two-shot lead over former PGA champion Collin Morikawa.
Oosthuizen, who shot a 6-under 64 in Thursday's opening round, was at 11-under 129 through the first two rounds at the course off Sandwich Bay, shattering the 36-hole British Open record first established by Nick Faldo in 1992 at Muirfield and equaled by Brandt Snedeker in 2012 at Royal Lytham & St. Annes.
"The game is good, but I know it's a really good leaderboard," Oosthuizen said. "I'll have to play good golf this weekend if I want to come out first."
Morikawa entered the clubhouse after shooting a 6-under 64, temporarily sitting atop the British Open leaderboard before Oosthuizen's late run. Morikawa's overall score of 9-under par was a 36-hole record for Opens held at Royal St. George's.
The American had seven birdies to just one bogey in the second round.
"I was just sticking to what I've been doing," Morikawa told reporters. "[Thursday], I thought I played really well. I wasn't hitting as many fairways.
"... Sometimes you have those days where you are very fortunate to have good numbers. Today was one of those days."
Morikawa, the 2020 PGA Championship winner, is attempting to become the first player in history to win two golf majors in debut appearances. He was one shot ahead of Jordan Spieth, who followed up his first-round 65 with a 67 to enter the weekend at 8-under 132.
Two-time major winner Dustin Johnson (65), Scottie Scheffler (66) and Dylan Frittelli (67) were tied for fourth at 7-under par. Justin Harding, Andy Sullivan, Marcel Siem, Daniel van Tonder and Emiliano Grillo were locked in a five-way tie for seventh at 6-under par.
British Open favorite Jon Rahm, who won the U.S. Open last month, rebounded with a 6-under 64 to jump 62 spots on the leaderboard. He was 1-over par in the first round and in danger of missing the cut before his bogey-free second round.
Phil Mickelson (72), Matt Kuchar (72), Branden Grace (71) and Patrick Reed (71) were among those who failed to make the cut. Stewart Cink, who ended the first day near the top of the leaderboard after his opening-round 66, shot a 77 in Round 2 to miss the weekend.
The 2021 British Open, the final major of the PGA Tour season, runs through Sunday at Royal St. George's.
The third round airs from 5 to 7 a.m. EDT Saturday on Golf Channel and from 7 a.m. to 3 p.m. EDT Saturday on NBC. Final round coverage airs from 4 to 7 a.m. EDT Sunday on Golf Channel and from 7 a.m. to 2 p.m. EDT Sunday on NBC.