Rory McIlroy's bid for a first, and rather unlikely, BMW PGA Championship title suffered an early blow as the second round got under way at Wentworth as his front nine score of 38 pushed him back down the field.

McIlroy announced on Wednesday that he had called off his planned November wedding to former world number one tennis player Caroline Wozniacki, even though the invitations had just been sent out.

The 25-year-old admitted he would therefore find it very difficult to concentrate on his golf in the European Tour’s flagship event, but did a commendable job with a first round of 68.

However, with a swirling wind making conditions difficult for the early starters, McIlroy missed from 15 feet for birdie on the first and then bogeyed the second after failing to get up and down from a greenside bunker.

Another bogey on the third left the former world number one — who had missed the cut here the last two years — on two under par, eight shots off the lead held by Thomas Bjorn, the 43-year-old Dane remaining top of the leaderboard as the delayed first round was completed.

Thirty-three players were unable to finish their rounds on schedule on Thursday after two delays caused by the threat of lightning, but none were able to get close to Bjorn’s brilliant opening 62.

Ireland's Shane Lowry had got closest with a 64 but was among the later starters on Friday, while Spain's Rafael Cabrera-Bello recorded an opening 65 and remained seven under with pars on the first two holes.

Matteo Manassero's defence of the title looked certain to end after two rounds as the 21-year-old Italian remained eight over par, while playing partner Justin Rose bogeyed the third to drop back to one under.

McIlroy repaired some of the damage with a birdie on the fourth, the downhill 552-yard par five which is playing the easiest hole on the course. And Cabrera-Bello did even better in the group behind, an eagle three taking the Spaniard to nine under par and within a shot of Bjorn.

Two-time winner Anders Hansen was producing the best round of the day so far, the Dane carding birdies at the fifth, sixth, eighth and 10th to improve to five under par.

McIlroy had enjoyed some good fortune on the seventh hole in round one, spinning a wedge shot some 30 feet back into the hole for an eagle, but it was a completely different story today.

The world number 10 thinned a bunker shot across the green and his pitch back onto the putting surface caught a slope to finish 25 feet away, from where he two-putted for a double-bogey six. At one under par he now had to be more concerned with making the cut than catching the leaders, with the cut currently predicted to fall at level par.

McIlroy made par on the 8th and 9th holes for an outward 38, five shots worse off than Thursday’s 33 for the front nine.