Medvedev up and running in US Open title defense

The Russian opened his campaign against Stefan Kozlov on Monday

World number one Daniil Medvedev began his US Open title defense with a straight-sets win over America's Stefan Kozlov on Monday, easing to a 6-2 6-4 6-0 victory.

Medvedev, 26, is aiming to become the first man since Roger Federer in 2008 to defend