Graeme McDowell's first round at the BMW PGA Championship ended in dramatic fashion when he was handed a two-stroke penalty after going into the bushes.
First his ball moved a fraction as he approached it at the 18th, and because he did not replace it, a second shot was handed to him by European Tour chief referee John Paramor afterwards.
"It's my fault," admitted McDowell after his round.
McDowell lies two over, along with fellow Northern Irishman Rory McIlroy.
Gareth Maybin is two under, four shots behind the first-round leaders, Scotland's David Drysdale and Ireland's Peter Lawrie.
The Ballyclare player was one of the early starters at Wentworth and posted a 72.
Darren Clarke was among the later players to tee off and he signed for a 71, which included four birdies and three bogeys.
McIlroy and McDowell have a lot of ground to make up after their disappointing opening rounds of 74 left them in a tie for 99th place by the end of the day.
McDowell moved to one under thanks to four birdies and three bogeys, but a triple bogey eight at the 18th saw him drop back to two over.
"I probably should have called for a referee - that would have saved me one shot, but what are you supposed to do - the whole area was sort of bouncing," added McDowell.
"I was aware of it and asked for it to be looked at. The rules are there for everybody's protection."
World number one McIlroy carded an eagle three at the fourth, and also posted three birdies in his opening 18 holes at the European Tour's flagship event.
The Holywood player's round was marred by five bogeys and a double bogey six at the par-four 16th.
McIlroy went out of bounds "by an inch" at the long 12th, something that was followed by him throwing a club in what he called "a release of frustration".
Michael Hoey is one over and Padraig Harrington four over, but Shane Lowry is in a better position to challenge on two under.
Jamie Donaldson, Justin Rose, Alvaro Quiros and Richard S Johnson are all tied for third on five under.
Maybin began his round poorly, with bogeys at the first and fifth holes, but improved to record birdies at the ninth, 10th, 12th and 14th.
Hoey had two birdies and two bogeys on his outward nine, but recovered to register three consecutive birdies between the 11th and the 13th.
He finished his round in catastrophic fashion with a double bogey six at the 15th and a double bogey seven at the 17th.