ISTANBUL (Reuters) - A dropped stroke at the last hole could not prevent Thorbjorn Olesen extending his overnight lead from six to seven shots after the third round of the $7 million Turkish Airlines Open in Antalya on Saturday.

The 26-year-old Dane, chasing the fourth European Tour victory of his career, hit a wild drive into the trees at the 18th and a bogey five meant he had to settle for a three-under-par 68 and an 18-under total of 195.

American David Lipsky (66), Bernd Wiesberger (66) of Austria, Italian Matteo Manassero (68), Englishman David Horsey (68) and China's Li Haotong (68) shared second place on 202 in the opening event of the tour's Final Series.

"It was a shame to bogey 18 but I just lost a little bit of concentration on that tee shot," Olesen told reporters.

"You get in trouble quickly here so concentration is the key tomorrow. I have never had a seven-shot lead so it does feel a bit weird but that is why it's so important to be aggressive and see if I can make a few birdies."

U.S. Masters champion Danny Willett, the only player in the top three of the money list competing this week after number one Henrik Stenson and third-ranked Rory McIlroy opted out, carded a 68 for 211.

The Final Series continues with the Nedbank Challenge in South Africa next week before the European season ends at the $8 million DP World Tour Championship in Dubai.

(Writing by Tony Jimenez; Editing by Steve Tongue)