Danny Willett extended his overnight advantage as the final round of the BMW International Open developed in Cologne.
Caught by home favourite Marcel Siem and Australian Marcus Fraser early in the round, the Englishman pulled clear with some solid golf as others found trouble in wet and windy conditions.
Willett – yet to win on The European Tour despite 19 top-ten finishes - returned to the outright lead when he knocked in a five footer at the third to be one clear.
The 24 year old stretched his lead to two with a precise tee shot to five feet at the short fourth to be two under for the round and 14 under for the tournament through seven.
Earlier Siem began the final round with a hattrick of birdies before coming unstuck approaching the turn.
The 31 year old from Mettmann – less than an hour’s drive from Gut Lärchenhof – holed an eight footer at the first, a 30 foot putt at the second and chipped to two feet at the long third.
But after three straight pars he went in the hazard twice at the short seventh and ran up a triple bogey six before going in the water again on the eighth and bogeying.
Australian Fraser was also in the water there and bogeyed, having began well with an approach to five feet at the first and two-putt birdie at the third.
Fraser was still in solo second at 12 under, one ahead of another Englishman chasing his first title – Chris Wood.
Paul McGinley recovered brilliantly from his disappointing third round 77 with a 66 to set the clubhouse target at ten under.
Willett’s par putt lipped out at the ninth as he turned in 35, but Fraser also bogeyed there so he was still two clear.
Fraser, looking for his third European Tour title, halved the deficit again with a brilliant 50 foot putt at the 12th.