Godolphin star Barney Roy claimed the third Group One of his career in the Grosser Dallmayr-Preis - Bayerisches Zuchtrennen at Munich.
Now a six-year-old, he won the St James's Palace Stakes in his younger days for Richard Hannon and went on to be narrowly defeated in the Eclipse.
Following a failed spell at stud, he was gelded and sent to Charlie Appleby before adding to his Group One tally at Meydan in March.
It looked a good opportunity in Germany to further supplement to his haul, but it was hard work for William Buick on the potential Australian spring candidate.
As the field turned into the straight, stablemate Spotify was better positioned in second with Barney Roy last and being ridden vigorously.
Quest The Moon pushed him all the way to the line, but Barney Roy held on by a neck with Patrick Sarsfield's winning run coming to an end in third.
"It was a very tough race. We thought beforehand that the German horses set a good standard and they were at home," Buick said.
"When the rain came this morning, we were a little concerned for Barney Roy because all of his best form is on fast ground.
"I thought he struggled on the ground from a long way out, but his courage and ability allowed him to win the race. He is a high-class horse."