Kaymer, 23, earlier followed up his impressive opening six-under-par 66 with a sublime seven-under effort in today’s second round to storm clear at the top of the leaderboard.

Stenson, starting the day at five under par, leapt to eight under after four holes following a run of three birdies and is on course to put real pressure on Kaymer – who shared the lead heading into the final day of August’s Scandinavian Masters before his only over-par round of the week scuppered his chances of a maiden European Tour title.

However,Stenson dropped back to two under, and seven under par overall, at the turn following a bogey five at the par-four fifth.

England’s Steve Webster and Spain’s Gonzalo Fdez-Castano are in the clubhouse on six under par, a stroke ahead of Ignacio Garrido and South African Airways Open champion James Kingston.

Defending champion Paul Casey is on course to miss the cut, which is projected to be set at one over par, after remaining at three over overall through nine holes of his second round.

Nick Dougherty and Darren Clarke moved on to one under overall after both picking up shots at the par-five 10th, while Open champion Padraig Harrington and compatriot Paul McGinley struggled to find form and remain at level par at the turn.

Overnight leader Kaymer, whose cool and calm nature was likened to seven-time Formula One champion Michael Schumacher by playing partner Simon Wakefield, carded eight birdies against just a solitary bogey.

“I am really satisfied with this round. Yesterday I was satisfied but today was amazing, I made a lot of putts,” said Kaymer, who recorded two victories on the Challenge Tour in 2006.

“I actually wasn’t playing as well as yesterday but my putting was better. On these greens it’s hard to make long putts but I made a couple today and that’s why I played well today.

“I was very nervous on the first tee yesterday but today I was totally relaxed.”

Kaymer is no stranger to low scores after shooting an incredible 13-under-par 59 at the Habsberg Classic in his native Germany on the third-tier European Professional Development Tour in June last year.

English trio Ian Poulter, Mark Foster and Anthony Wall are all in the clubhouse on four under par alongside Sweden’s Robert Karlsson, a stroke clear of Lee Westwood who slipped back to three under following a second-round 73.

Kaymer’s round is even more remarkable considering world number eight Adam Scott slipped back to two under par overall following a second-round 74.

Two-time PGA Tour winner Luke Donald could meanwhile only manage a 73 to drop down to level par alongside Colin Montgomerie, who carded a second-round 72.