Rory McIlroy birdied his last hole to pace Danny Willett in their chase for the Race to Dubai trophy on the opening day of the World Tour Championship on Thursday.

McIlroy chipped in from a greenside bunker on the 18th hole to card a 4-under-par 68, tied with English golfer Willett, two shots behind the four leaders.

The pair are the main contenders to finish No. 1 for the season in the European Tour finale, McIlroy for the third time in four years, and Willett for the first time. Five others are in contention, but whoever finishes higher between McIlroy and Willett is expected to claim the trophy.

Martin Kaymer, English pair Ian Poulter and Andy Sullivan, and Australian Marcus Fraser topped the leaderboard with 6-under 66s at Jumeirah Golf Estates.

Two-time defending champion Henrik Stenson dropped five shots in his last four holes to finish on 77.

McIlroy made the turn at 2 under, bogeyed the 10th, recovered with back-to-back birdies, and capped his round with an accurate chip off his fourth shot.

Sullivan eagled the par-5 7th, and Fraser was 7 under through 14 holes but bogeyed the 16th to fall into the tie for the lead.

Francesco Molinari, on 67, was between the leaders and McIlroy, Willett and six others on 68.

Justin Rose, who was third in the Race to Dubai, made successive bogeys in his last two holes in a 1-under 71.

Patrick Reed was one shot better.