David Horsey recovered from a shaky start to extend his overnight lead to four shots after the second round of the Russian Open in Moscow.
Late birdies on Thursday had given Horsey a one-shot lead after a round of 65, but - having started on the 10th hole on Friday - bogies on the 12th and 13th saw him relinquish that advantage.
But he birdied the 14th, 17th and 18th to recover and, after bogeying the first, he picked up four more shots over his final six holes to sign for a 68 to sit on 11 under at half-way.
That puts him two shots clear of Thomas Pieters, who also carded a 68 on Friday, with Scotland's Peter Whiteford a further two shots back after a double-bogey on the 15th meant he could do no better than a 71.
Kevin Phelan is the leading Irishman in the field after a round of 70 saw him finish six shots off the lead in a share of ninth.
"I got off to a slow start but I managed to bounce back well," Horsey told the European Tour website.
"I tried to do the same as yesterday and stick to my game and not worry about much else.
"Dropping a couple of shots early on is always disappointing, but I knew there'd be plenty of chances to come and I just needed to stay patient and keep giving myself putts for birdie.
"I've got a while now until the next round, so I'll be recharging the batteries this afternoon and hopefully I'll be raring to go tomorrow."
Although his double-bogey could yet prove costly, Whiteford was happy to still be in contention after eight consecutive missed cuts.
"The start was shocking," he said. "The first tee shot was straight in the rubbish, and I was four over after five holes. But it was a good fightback.
"Strangely, I felt like I was swinging it better today, but there are still some absolutely wild ones in there which cost me today. The good shots are really good, but there are some calamities.”
Whiteford ended up in a tie for third alongside England's Gary Boyd, who catapulted himself up the leaderboard with two late birdies, moving ahead of a four-way tie for fourth.
That group included Scotland's Scott Jamieson, whose round of par 72 was six shots off the pace he set on Thursday.