AMSTERDAM – Unheralded Callum Shinkwin shot five birdies and an eagle Thursday on his way to a 6-under 66 and a one-shot lead after the first round of the 100th edition of the KLM Open.

The 26-year-old British golfer is ranked No. 446 and hasn't made the cut in his last three tournaments since the British Open as he struggled with illness and a back injury. But he started with a birdie on the second hole and an eagle on the third, before making his lone bogey on No. 5. He finished with two more birdies on Nos. 16 and 18 to sit one shot clear of a group of seven players, including Gavin Green.

Sergio Garcia was among eight players sitting two shots behind Shinkwin.

Joost Luiten, who won this tournament in 2013 and '16, started badly with three bogeys in his outward nine holes before making six birdies on his back nine to leave him level with defending champion Ashun Wu and seven others on 69.