 Complete the following phrase:  Over the last few decades, swiss tennis players Roger Federer, Stan Wawrinka and Martina Hingis have been at the top of tennis. Federer, Wawrinka and Hingis all have Grand Slam singles titles to their names. Federer has won 20 Grand Slam titles and holds the record for the longest consecutive stay as the world number 1 at 237 weeks. Federer has won a record 8 Wimbledon titles overall and has also won the Australian Open 6 times, the US Open 5 times and the French Open once. Another Swiss tennis figure is Marc Rosset, winning the singles gold medal at the 1992 Olympics. Both Federer and Wawrinka teamed up at the 2008 Olympics to win the doubles gold medal. Federer and Wawrinka had a massive influence in Switzerland winning the Davis Cup title in 