Andy Murray calls for tougher drug testing in tennis

Andy Murray has admitted that he thinks more can be done in the fight against drugs in sport.

The US Open champion believes that the element of surprise remains remains a strong weapon for drug testers and has called for more to done by the International Tennis Federation.

He told The Telegraph: "You never know in any sport what's really going on.

"I think the out-of-competition stuff could probably get better. When we're in December and stuff, when people are training and setting their bases, I think it would be good to try and do more around that time.

"On Saturday night, we actually had a blood test. They came to the hotel late that night, it was completely random. I think that's good, we're not used to doing that many blood tests in tennis and it's something that's obviously necessary."

Murray begins his Paris Masters campaign on Wednesday with a second-round match against either Paul-Henri Mathieu or Roberto Bautista-Agut.