The gifted 26-year-old from Perth, a six-time pro winner still seeking his breakthrough triumph on the PGA Tour, recorded seven birdies and just one frustrating bogey at his final hole as he took the early second-round clubhouse lead at TPC Sawgrass.
At 11 under for his two rounds following an opening 67, Lee was level at the top with American Akshay Bhatia, who matched Lee's 66, while another US player JJ Spaun, the joint first-rounder leader, was one behind after his 68.
Rory McIlroy also enjoyed an impressive second round, making six birdies in his first 11 holes, but a poor finish with two late bogeys meant he ended up with a 68 to lie two shots adrfift of Lee.
Another major winner Collin Morikawa had nine birdies in his 65 to join McIlroy on nine under.
But while Lee is in fine shape for the weekend, he'll have been irked by his finish at the long ninth hole, his last, where he was looking to make an eighth birdie of the day, but only ended up making a mess of his approach.
Lee had found the middle of the fairway with his tee shot, but sent his 300-yard follow-up into the rough stuff at the right of the green, and could only flop his chip into a small bunker.
He still couldn't find the green from there, and ended with a six, just his second bogey in 36 holes.
It was a far cry from his earlier excellence on Friday as, starting off from the 10th hole just a shot off the overnight lead, he birdied his opening hole with a 10-footer and went on to record six more birdies while particularly peppering the flag on his inward push.
Lee, who's nicknamed 'Chef' for his ability to really 'cook' on the fairways, got on a hot streak in successive holes between the third and the fifth, arrowing approaches to four, six and 11 foot respectively and sinking all three putts.
