Australian Scott Hend shot the joint-lowest round of the week to take a one stroke lead at the BMW International Open in Germany.
Continuing windy conditions brought the punishing rough into play again at Golf Club Gut Laerchenhof near Cologne, but the 44-year-old avoided most of the trouble to shoot a 67 to go six-under par.
Hend bogeyed the 10th, his opening hole, to drop back to level par but it was his only blemish as a birdie on the 12th was followed by an eagle at the par five 15th before a birdie three at the 17th took him into a share the lead.
He closed his second round with back-to-back birdies to card a 67 that leaves him one shot clear of Chile's Nico Geyger and Henric Sturehed of Sweden.
British rookie Aaron Rai briefly assumed the outright lead at seven under, helped by a hole in one with a six iron at the 167-yard 16th which won him a €125,000 BMW i8 Roadster courtesy of the tournament sponsors.
However, he mis-hit his approach to the sixth into the water guarding the front of the green and double-bogeyed, dropping another shot at the next but recovered to close with a 71 to be four under par.
"It was a tricky pin position and it was kind of downwind as well," said the 23-year-old, who graduated from the Challenge Tour after winning three events last season.
"I actually wasn't playing to get in pin-high, I was playing a little long then it pitched short, bounced perfectly and rolled up and went in."
Two-time major winner and home favourite Martin Kaymer carded a 68 to move alongside Rai, overnight leader Sebastien Gros, Maximilian Kieffer and Australian Nick Cullen in a share of fourth.
Former Masters champion Sergio Garcia hit a brilliant approach to two feet at the par-five 15th for eagle - and then birdied the 17th - to reach one under and ease any fears of missing the cut.
The line eventually fell at four over, meaning world number 10 and US Open runner-up Tommy Fleetwood made the weekend courtesy of a six-foot birdie putt at his final hole for back-to-back 74s.