Marcel Siem clubbed a second successive 68 to finish one shot clear of Alexander Noren as the players head into the third round of the French Open.
The German fired five birdies during his second round, but dropped two shots at the 17th to leave himself on six-under for the championship.
Noren also shot five birdies during his best-of-the-day round of 67 at Le National in Paris.
Anders Hansen and George Coetzee both carded rounds of 68 and lurk well within striking on four-under, with David Lynn, Francesco Molinari and homegrown favourite Raphael Jaquelin trailing on three-under.
