Tapio Pulkkanen fired a battling bogey free 66 to take a one shot lead into the weekend at the South African Open hosted by the City of Johannesburg.
There was a seven way tie for the lead at one point on an enthralling day at Randpark Golf Club but a pair of birdies combined with some excellent scrambling on the way home saw Pulkkanen get to 11 under.
That left the Finn a shot ahead of England's Sam Horsfield, 18-year-old amateur Jayden Trey Schaper and South African trio Jaco Ahlers, Trevor Fisher Jnr and Thriston Lawrence.
Pulkkanen has been a picture of consistency since topping the European Challenge Tour Rankings in 2017 and he has brought that quality to Johannesburg this week.
The 29-year-old has not dropped a shot since his third hole in round one as he looks for a first European Tour win, with play over the weekend being on the Firethorn Course where he was bogey free on the second day.
"It was a really good round, it was a lot of grinding," he said. "I started well and made three birdies in six holes. After that I didn't hit many fairways and had to grind for pars.
"I've had ten weeks off from tournaments - a long, long break for me - and I went to the US to practise and I think I found my game a little bit so I feel comfortable right now."
Pulkkanen birdied the third and fourth and another gain from ten feet on the fifth had him in a share of the lead.
He made an impressive save on the next to start a run of eight straight pars and it was Horsfield and Lawrence who edged ahead.
It was a really good round, it was a lot of grinding. I think I found my game a little bit so I feel comfortable right now - Tapio Pulkkanen
Horsfield started his day with ten straight pars but holed from the fringe on the 11th, made a two putt birdie on the par five 14th and put his tee shot to five feet on the next to get into double figures.
Lawrence birdied the fifth, eighth, ninth and 12th before making an 18 foot eagle putt to catapult himself into a share of the lead.
Pulkkanen made a nice up-and-down on the 14th to share top spot and a tee shot to four feet on the next saw him jump out on his own but he soon had playing partner Ahlers for company.
The 37-year-old holed a very long putt on the 11th to add to gains on the fifth and seventh and an excellent tee shot on the 15th had him within two of Pulkkanen.
An 15 footer on the 16th was followed by a 20 foot effort on the next as Pulkkanen fought to save par and, after both men hit poor tee shots on the last, Pulkkanen saved par again where Ahlers could not.
Schaper birdied the sixth but dropped shots on the seventh and eighth before gains on the 11th and 12th steadied the ship.
A wonderful bunker shot on the 14th set up a birdie and another followed after an excellent tee shot on the next before the South African hit a stunning approach from the rough to ten feet at the 16th to get to double figures.
Fisher made a hat-trick of gains from the third to share the lead but another birdie on the 12th was sandwiched by two bogeys before he made an eagle on the next.
American Johannes Veerman had led by two at one stage at 11 under but he slipped back to nine under alongside home favourite Daniel Greene and English duo Harry Hall and Jack Senior.
There were then 12 players at eight under including defending champion Louis Oosthuizen, fellow South Africans George Coetzee and Branden Grace, and 2015 winner Andy Sullivan.