Published: Sep 08, 2011 2:07 PM EDT
Updated: Sep 09, 2011 6:30 AM EDT

HILVERSUM, Netherlands (AP) - Aiming for his third KLM Open title in six years, England's Simon Dyson shot an opening round five-under-par 65 Thursday to tie for the lead with Marcel Siem on a day marred by vandals and torrential rainfall.

Play was initially delayed for 45 minutes after vandals dug up parts of four greens at the Hilversum Club. Later, heavy rain soaked the course, forcing players off for more than three hours.

Unfazed by the delays, Dyson shot an eagle at the 443-meter (484-yard) par 5 12th and had five more birdies and two bogeys. He won the event in 2006 and 2009 on the Kennemer course.

"That's probably the wettest course I've ever played," Dyson said as he dried off in the clubhouse.

Siem also eagled the 12th and the German had four birdies and a single bogey in his 65.

Defending champion Martin Kaymer struggled to 3 over after 15 holes before the rain delay and he added another bogey when he returned to card a four-over 74.

Lee Westwood, who won the tournament in 1999, shot back-to-back bogeys on holes 5 and 6 but recovered with birdies on the next two holes before play was called off in gathering darkness with 78 players yet to complete their first round.

U.S. Open champion Rory McIlroy got off to a slow start, with a bogey five on the third to be one-over after eight holes by the end of play.