The 46-year-old covered the opening eight holes in seven-under-par at Bernardus Golf in Cromvoirt, reeling off three birdies in a row from the second then going birdie-eagle-birdie from the sixth.
The early burst set up a seven-under-par 65, moving Drysdale into a tie for 12th on seven-under, five shots behind leader Kristoffer Broberg of Sweden.
“I just got off to a hot start,” he said of his day’s work. “I had a short putt for birdie on No 2 and then hit a wedge stone-dead to just a couple of inches on three.
“I then hit a lovely hybrid shot to around four-feet from the hole at the par-3 sixth.
“Then, at the par-5 seventh, I had exactly the same number as I had on three which was 101-yards, so I hit the same shot and it went in.
“I then birdied eight but then I ran out of steam a wee bit. I played steady enough for the next 10 holes but just didn't have anything really going.
“I took bogey from the middle of the fairway on 16 and then did well to get up and down from the slope on 18 for par.
“So, overall it was a great day’s golf and I would have easily taken that at the start of my round but then it could have been better. Golf is like that as we’re never fully happy.”
Drysdale, who is bidding to hang on to his European Tour card for the 18th consecutive season, moved inside the safety zone after last week’s BMW PGA Championship.
He’s looking to give himself some breathing space for the final few weeks of the campaign and said: “I enjoy the golf course as it’s got a Scottish links feel about it and it was designed by Kyle Phillips, who designed Kingsbarns Links.
“The course here even has the same grass on the greens as Kingsbarns Links, so I am feeling quite at home and looking forward to the weekend.”
Euan Walker added a 72 to his opening 67 to progress comfortably on five-under two better than David Law, who had an eagle and five birdies in his 69.
Broberg put his injury problems behind him to fire his lowest European Tour round for almost six years and lead the way at the halfway stage.
The Swede made nine birdies with a single dropped shot as he carded a 64 that moved him to 12 under, a shot clear of Belgian Thomas Detry and Dane Marcus Helligkilde.
On the Ladies’ European Tour, Kylie Henry sits one shot off the lead, held by home home player and Solheim Cup star Celine Boutier, after the second round of the Lacoste Ladies Open de France.
The Scot fired in one of the rounds of the day at Golf Club de Medoc with a scintillating six-under 65, with seven birdies and a single bogey to her name.
“It was a really solid day of golf, I’m really happy with my game,” said Henry, who is bidding to land a first win since the 2014 German Ladies Open.