Top seed Roger Federer lost to Argentine qualifier Federico Delbonis in the semi-finals of the German Tennis Championships in Hamburg.Federer, 31, had been trying out a larger, more powerful racquet frame in Hamburg after losing in the second round of Wimbledon last month.
The world number five will play at the Swiss Open in Gstaad next week.
Federer had taken a wild card for Hamburg and Gstaad as he looks to find some form, and try out the new racquet, after losing in the quarter-finals of the French Open and round two at Wimbledon.
The Swiss will then head to the American hard courts ahead of the US Open, which begins on 26 August.
Delbonis, 22, goes on to face Italian Fabio Fognini in Hamburg on Sunday, and the Argentine left-hander will be playing in his first ATP final after coming through two rounds of qualifying and five matches in the main draw.
– BBC Sport
