LONDON — Roger Federer believes tennis players should undergo more anti-doping tests to ensure the sport does not suffer the problems that have plunged athletics into crisis.
The Swiss 17-times grand slam champion said he was still surprised when he walks off court and is not routinely asked to provide a doping sample.
He has also called for more out-of-competition tests.
Speaking at a news conference at London's O2 Arena where the ATP World Tour Finals begin on Sunday, the 34-year-old said: "I think they are trying their most but we can do more.
"Whenever you make the quarter-finals of a tournament, when the points are greater, the money is greater, you should know that you will be tested.