Xavier Bettel watched the tense game between the Luxembourg sportsman and Marin Cilic, along with crown Prince Guillaume, with which he was photographed by Reuters.
It was the second game since Muller’s incredible Monday performance when knocked out favourite Rafael Nadal in a five-set tennis match.
Not one to miss out on a promotional opportunity, Bettel posted two photos on Twitter: one of himself apparently giving an interview with Sky Sports and the other (below) of a water bottle bearing the Luxembourg brand logo, with the court in the background.
