Oosthuizen was in scintillating form as he consolidated his excellent first round to lead the field heading into the weekend at Royal St. George's.
Oosthuizen Leads For Second Consecutive Day At Thrilling Open
It was déjà vu on Friday Royal St. George's as an effortless, near-faultless Louis Oosthuizen took the clubhouse lead at the 149th Open Championship.
The South African's 65 complimented his 64 on Thursday and he did it in his similarly serene, calm manner on a warm, breathless day on the Kent coast.
His score of 129 after two days set a new record for lowest score at The Open Championship after two rounds.
Oosthuzien's front nine was steady - two birdies and seven pars - as he slowly caught up Collin Morikawa's 9-under par clubhouse lead.
After making a stunning eagle on the 14th to take his cumulative score to 12-under, the South African made his first bogey of the weekend on the 16th but followed that with two sensible pars.
His par on the 18th left him 11-under for the tournament, two ahead of American Morikawa in second place, as he held the overnight lead for the second consecutive day.
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Morikawa set the early pace on Friday morning, and his sparkling 64 left him at 9-under for the championship - a three shot cushion before the afternoon starters came out.
His 64 at one point looked like being 61 and, when he was 7-under through 14 holes, the lowest Major round looked in his sights
However, the excitement waned as bogey and four pars consolidated a nonetheless excellent round from the American making his Open debut.
Jordan Spieth sits third - 8-under par for the tournament - after shooting 67 to go with Thursday's 65.
He threatened to get even closer to Oozthuizen's total, but a quiet back nine leaves the 2017 champion nicely placed with his game looking well under control at Royal St. George's.
Those at 7-under par include Dylan Frittelli (67), Scottie Scheffler (66) and Dustin Johnson (65) and all three would consider themselves right in the race for the Claret Jug.
Early morning starters Emiliano Grillo and Daniel van Tonder shot 64 and 66 respectively to sit at 6-under for the championship - a score that looked like it would be only be a handful shots off the leaders before the afternoon wave began.
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The afternoon starters seemed to feed off each other's scoring and John Rahm (64), Brooks Koepka (65) and Ian Poulter (66) were some of the big names to make a move through the field.
Despite the course visibly drying out as the day went on, scoring in the afternoon was much easier than on Thursday as the wind died down and birdies became plentiful.
Defending champion Shane Lowry recovered smartly from a poor first day, shooting a crowd-pleasing 65 to get himself back in contention to successfully defend his Claret Jug.
The cut line hovered between level par and +1 throughout the day and, as those on +1 looked more and more likely to be safe, some big names were forced to grind their way under par.
Some significant names who missed the cut included Tyrrell Hatton, 2018 champion Francesco Molinari, Patrick Reed and Phil Mickelson, who finished the tournament at +12 after his round of 80 on Thursday.
Bryson Dechambeau fought hard to make it into the weekend and his four birdies and four bogeys culminated in a round of 70 - squeezing him into the weekend by one shot.
Will Zalatoris was forced to withdraw before he got his second round underway after an incident on the 15th hole on Thursday left him with a leg injury he couldn't play through.
Elsewhere on another thrilling day at The Open, Jon Thompson had an ace on the 16th hole which saw him secure his place for the weekend.
Meanwhile, Matthais Schmid's 65 was joint best round by an amateur in the history of The Open, tying Tom Lewis' record which also came at Royal St. George's 10 years ago.
It has set up the weekend perfectly. A stacked leaderboard, a drier Royal St. George's and nearly full grandstands should make for great viewing as the 149th Open Championship heads towards its dramatic climax.
