The game’s hottest player, Brooks Koepka, birdied his final hole to join fellow American Jamie Lovemark at 10-under and atop the leaderboard through 36 holes, one ahead of Scott whose 64 was the best round of the day.
World Number One and FedEx Cup leader Dustin Johnson is outright fourth a shot further back after an extraordinary 67 that began with a triple bogey.
Johnson went on to post eight birdies against one other dropped shot to sign for a 4-under score and be just two shots off the lead.
Scott endured a frustrating 2018 prior to his sudden resurgence at Bellerive but looks to be riding a wave of momentum with some stunning play at Ridgewood Country Club Friday.
A brilliant ball striking round even by his standards, it is a hot putter that has him in contention picking up more than three stokes on the field on the greens.
With eight birdies against a lone bogey he leapfrogged 24 Players, an eight-foot putt for par on the final hole sending him to the weekend with some confidence.
“I played well yesterday but I hit a few more fairways so I had a few more shots at the green and created a couple more chances,” he told Golf Channel after his round.
“I think my putting was really good too. I holed the putts you’d hope to make today, including the one on the last, so that feels really good to finish a round off really clean when I played well.”
Scott continues to carry two putters, something he began a month ago, but says he has had little call to use the short one.
“The idea was to use the short putter on some really long putts and generate a little speed more easily,” he said.
“Something like 20 footers. I found this year I didn’t make the 20 footers so I’ve been working really hard with the short putter but I haven’t had to use it much.
“I think I scared the long putter into performing a bit better.”
Scott is the best of the Australians but not the only one in the mix with Jason Day and Cameron Smith both inside the top 20 after solid rounds of golf.
Day signed for a 5-under 66 but will be disappointed with his finish after making a double bogey at the last thanks to finding brutal rough off the tee.
Blemish free for the first 17 holes Day missed the fairway left and took two shots to extricate himself before missing from 10 feet for bogey.
It was a disappointing finish to an otherwise outstanding round, Day notching seven birdies to that point to be inside the top 10.
Both he and Smith finished the day at 5-under and T16, Smith after signing for a 3-under 68 to go with an opening 69.
Four birdies and a bogey from the Queenslander, who lies 53rd on the Fedex Cup standings, was a solid performance as he tries to play his way into the top 30 and a berth in the TOUR Championship in three weeks’ time.
Marc Leishmn has less concerns about qualifying for the season ending event but was in danger of missing the cut early in his second round when he drifted three shots outside the number with a bogey at the sixth.
An opening 2-over 73 meant he would need to find something Friday and after turning 1-over he did, reeling off four birdies in a five hole stretch from the 12th.
He ultimately signed for a 2-under 69 to qualify on the cut mark and will be looking to move up the leaderboard at the weekend.
Tiger Woods also finished even par through two rounds with back to back rounds of 71 while Justin Rose and Jon Rahm were among the notables to miss the weekend’s play.
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