Korea's Byeong Hun An made an excellent start to the defence of his title when the BMW PGA Championship got under way in perfect conditions at Wentworth.
An was ranked 132nd in the world when he carded a final round of 65 last year to set a tournament record of 21 under par and finish six shots clear of the field, becoming just the third player to win the European Tour's flagship event on debut.
The 24-year-old returned to the event ranked 26th after a victory on home soil in Korea and nine top-10 finishes around the world, including losing out in a play-off for the Zurich Classic of New Orleans earlier this month.
And the former US Amateur champion continued that form in the early stages of the £3.8million event on Thursday, carding birdies on the fourth, fifth and sixth to share the lead with Spain's Jorge Campillo.
Campillo was in the second group out at 0710 and had gone to the turn in 33 before picking up his third birdie of the day on the 10th, with Italy's Edoardo Molinari and Ireland's Shane Lowry a shot behind.
Molinari, who retired with a wrist injury after playing 16 holes in eight over par last year, had birdied the second and fourth, and Lowry had both birdied the second and fourth, with former world number ones Luke Donald and Martin Kaymer on one under after also taking advantage of the par-five fourth.
Source: PA
