According to the three-times Wimbledon champion, the season is so long and gruelling that many players need drugs to get through it.
'Why shouldn't there be doping in a sport where there is so much money?' the 26-year-old German said.
The Association of Tennis Professionals says it conducts drug tests and that no player had ever tested positive. Asked if he doubted that, Becker said: 'Yes. I am not saying it had to be anabolic steroids, but coke, speed or marijuana, for sure.
'The question is whether the ATP would allow a positive drug test to come through, because the whole scene would fall into disrepute and the sponsors would really run away.'
Despite completing the worst year of his career, Becker, whose girlfriend, Barbara, is expecting their first child shortly, insists he still aims to become the world No 1 under the guidance of his new coach, Nick Bollettieri.Reuse content