Defending champion Danny Willett put aside concern for his ailing back to burst into a share of the the lead on day two of the BMW International Open in Munich.

Willett posted a second round seven under par 65 in superb conditions to move to 10-under par before being joined by Austrian Bernd Weisberger who birdied the last in a 68 after starting with a 66.

Germany’s Martin Kaymer, winner of the event in 2008, is one shot back but failing to take full advantage in adding a 71 to his opening 64.

Willett had been observed late on Thursday afternoon lying flat out on the floor in the locker room of the Munchen Eichenried course as a physio worked on his shoulders and back.

The Callaway staff player arrived in Munich first a first event since withdrawing from last month’s Nordea Masters in Sweden and the result of a back complaint he traced back to incurring during the staging earlier this year of the Omega Dubai Desert Classic.

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