Martin Kaymer surged to the top of the leaderboard yet again at the Abu Dhabi HSBC Championship by carding another six-under 66 on Friday.

The steely German put himself in with a great chance of winning the European Tour event for a fourth time by opening up a one-shot advantage over Rafa Cabrera Bello at the halfway mark.

Kaymer was two shots back from overnight leader Henrik Stenson at the start of the day, but put on an exhibition on the back nine at the Abu Dhabi Golf Club to hit the front on 12 under.

The two-time major champion was one over for the day when he teed off at the eighth, but sunk an eagle putt from around 20 feet to kick-start his second round.

There were six birdies after the turn for the former world number one, whose only other blemish came when he dropped a shot at the 12th.

Kaymer, who has managed two top-three finishes in this competition as well as the three wins, said: "I don't try to push, I just try to enjoy playing my favourite golf course,

"Once in a while when a putt drops in you catch momentum and you can make another three or four birdies coming in, like it happened today."

Cabrera Bello matched Kaymer's round to keep himself firmly in the hunt for a first title since his 2012 Omega Dubai Desert Classic success.

The Spaniard set the clubhouse lead after going out in the morning, finishing with three consecutive birdies following his only bogey of the day at the sixth.

Tommy Fleetwood, Paul Dunne and Kiradech Aphibarnrat are well poised just two shots adrift of Kaymer, while Open champion and last year's Race to Dubai winner Stenson dropped back to nine under after signing for 71.