Tapio Pulkkanen moved into pole position at the South African Open on Friday, with defending champion Louis Oosthuizen three shots off the pace.
Pulkkanen, yet to claim a win on the European Tour, shot a five-under 66 on the Firethorn Course to take a one-shot lead on 11 under for the tournament after two rounds in Johannesburg.
Jaco Ahlers could have gone into moving day level with the Finn after birdies on the 15th, 16th and 17th, but a costly bogey at the last saw him slip into a group of five players on 10 under.
Thriston Lawrence was also part of the tie for second after carding four birdies and an eagle in a flawless 65, with amateur Jayden Trey Schaper keeping him company after going five under on the back nine.
Oosthuizen signed for a two-under 69 to drop into a share of 11th with Branden Grace. Overnight leader Johannes Veerman was unable to match his stunning 62 in round one, slipping to a four-way tie for seventh on nine under with an even-par 71.