ST. OMER, France -- Christian Nilsson shot a 1-under 70 Saturday to retain his two-stroke lead after the third round of the $1.2 million St. Omer Open on the European Tour.

The Swede increased his lead to three strokes with birdies on the 11th and the 12th, but had a double bogey on No. 17. He recovered with a birdie on the 18th to finish at 4-under 209.

"It felt great to make a birdie on the last hole to make up for the disappointment of the double bogey," said Nilsson, who is ranked 534th in the world after finishing seventh at the Italian Open last month.

Robert Coles of England had the best score Saturday, a 66 that moved him into a tie for second two shots back with Francois Delamontagne. The Frenchman had a bogey-free 67.

"I made a few good saves today, and that is the key to low scores around here -- your putting," Delamontagne said. "I know the course very well, so that's a big advantage."

John E. Morgan of England slipped from second place to eighth after a 73 to slip that gave him a 214 total.

Nilsson's lead could have been even greater had he not double bogeyed the penultimate hole, but a nine-foot putt on the 18th ensured his third birdie of the day and restored his two-shot advantage.

Belgian Nicola Vanhootegem and Wales' Liam Bond are the only other players bettering par on 1 under after rounds of 69 and 70, respectively.

Nilsson, 29, parred every hole on the front nine and then accelerated on the way back, firing back-to-back birdies on the 11th and 12th. He had not dropped a shot for 34 holes until the par-3 17th ended that run.

"I was really happy to finish like that after what happened on the 17th," said Nilsson, who is chasing his first European Tour win. "I had a long, tough putt, which I overhit and had to chip back but I needed to let it go, forget about it and I did.

"I'm feeling really good. My game from tee to green was great," he added. "Sunday is going to be a similar experience to this so hopefully I'm prepared for it."

Chasing Nilsson will be Coles, who posted his best round of the season to be tied for second. The 35-year-old has been off his game of late but found a rich vein of form on the front nine here, where he hit five birdies.

A double bogey at the par-4 12th halted his rise up the leaderboard, but he picked up two more birdies on the 13th and 17th to be well placed for the final round.

"I just got on a little run," said Coles. "There are some tricky holes but there are some where you can hit it quite close.

"I haven't really played very well this year. I've struggled with the putter and when that was better my irons weren't great so it's been very mixed," he added. "But here I managed to bring it all together."

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