Britain's Andy Murray celebrates with the trophy after winning the men's singles final on the eighth and final day of the ATP World Tour Finals tennis tournament in London on November 20, 2016. / AFP / Glyn KIRK (Photo credit should read GLYN KIRK/AFP/Getty Images)

Britain's Andy Murray celebrates with the trophy after winning the men's singles final on the eighth and final day of the ATP World Tour Finals tennis tournament in London on November 20, 2016. / AFP / Glyn KIRK        (Photo credit should read GLYN KIRK/AFP/Getty Images)