World number five Alexander Zverev defeated world number 25 Karen Khachanov in men's singles tennis final to clinch gold medal at Tokyo Olympics. Zverev, who ended Novak Djokovic's Golden Slam bid by knocking him out in semi-finals, won the final in straight sets (6-3, 6-1). Zverev is the first German to win an Olympic gold in singles tennis since 1988.