Andy Murray says world rankings rightfully determine best player

Andy Murray says whoever tops the rankings at the end of the season will rightfully be the world's best tennis player.

He's currently number two but has been chasing top-ranked Novak Djokovic after victories at Wimbledon and the Olympics.

Murray starts his Vienna Open campaign against Martin Klizan of Slovakia tomorrow.

He tells Sky Sports News he's happy to acknowledge who's number one for now.