The 27-year-old, fresh from winning the Arnold Palmer Invitational at Bay Hill last weekend, carded a second successive 69 at TPC Sawgrass to reach the halfway stage in the $15 million sitting on six-under-par.
DeChambeau has now signed for seven straight rounds under par at the Ponte Vedra Beach venue, but his good work so far in the game’s so-called “fifth major” has not been down to his prodigious power off the tee.
At the time he finished his second circuit, the US Open champion was ranked 77th in the field in strokes gained off the tee and, by his own admission, he’d been fortunate to get away with some wayward hitting over the opening 36 holes.
“I'm happy with the fact that I've still been able to keep myself in it and score well,” said DeChambeau. “I've been pretty lucky, for the most part. I don't think that'll happen this weekend.
“I've got to make sure that my game is good off the tee, so I don't have those issues occurring and I don't have to rely on luck. I have to get it in the fairway.”
Missing that at his opening hole - the tenth - led to a double-bogey 6 to start the second circuit, but birdies at the 11th, 16th and 17th got him back on track before further gains at the sixth and ninth completed a good day’s work.
“Oh, frustration, definitely,” said DeChambeau of the start, who is a combined 29-under for his last nine round since signing for a 77 in the opening round of the WGC-Workday Championship at The Concession a fortnight ago. “You don't expect to do that the first hole out, especially as I was hitting it pretty good this morning."
“I'm a perfectionist, and I'll continue to be so until the day I die and until the day I stop playing this game,” he added of his performance so far this week.
“That's just the way I am. I love it about me, that's what makes me work hard and fight for every shot out there.”
On a day when overnight leader Sergio Garcia was among the later starters, American Chris Kirk carded an eagle and seven birdies to sign for a 65, which catapulted him to seven-under-par.
“I wish I had some revelation of something that I changed and sparked this incredible play, but I didn't change anything,” said world No 84 Kirk, who recorded the last of his four PGA Tour triumphs in 2015.
Helped by a hole-in-one at the third, Denny McCarthy joined DeChambeau on six-under, as did Charley Hoffman and left-hander Brian Harman, with Spaniard Jon Rahm moving to four-under on the back of a 68 that saw him cover the last 12 holes in five-under.
Martin Laird, a runner-up in this event in 2012, picked up two shots in his last six holes for a 71 and a one-under total, which looked likely to make the cut.
Russell Knox and Bob MacIntyre both reached the turn in their second rounds with chances of doing likewise on level-par and one-over respectively.