Roger Federer's coach lists the Swiss' career-best moments

Coach Severin Luthi says Roger Federer's two Grand Slam victories in 2017 have definitely been one of the most moments in his career.Federer, 41, underwent a knee surgery in the summer of 2016. When Federer returned in 2017, he was 35 and coming off of a major knee surgery. But Federer proved the doubts wrong as he won the Australian Open and Wimbledon titles that year. Also, Luthi named Federer's victories at the 2009 French Open and the success he had while representing his coun