Prior to 2011, the ITF's anti-doping rules for in-competition testing stated: "...in addition to any other Players that the ITF selects for Testing, all finalists and losing semi-finalists in each Competition at a selected Event will ordinarily be tested." (See F.3 in the 2010 Rules)
However, the following change was made for 2011:
F.3 A requirement to test every player who reaches the semi-finals of the competition is no longer appropriate. Modern test distribution methods are more sophisticated than that. Removing the requirement gives the ITF the flexibility to decide (in conjunction with its partners) how best to allocate its testing resources. (See here and here)
Do you recall any member of the media reporting this?
Worth The Risk? (Added January 9)
Arf poses an interesting question in the comments. Is it worth the risk to dope in-competition? Actually, the question should be, is it risky to dope in-competition?
Here are some numbers to think about:
|Possible Resting Opportunities versus Actual Samples Taken|
At the 2010 Australian Open, the ITF took 78 male specimens for doping tests. Those 78 samples covered singles, doubles, and mixed doubles. If the ITF tested every male player after every match played then they would need to take 568 samples. Thus, the 78 samples they actually took represents 13.7 percent of the total potential samples available to be taken. And 8 of those 78 samples would have been taken for the singles, doubles, and mixed doubles finalists.
What does this mean? First, it means that unless you make the finals, you're not likely to get tested. Second, it means that if you make the finals, that will likely be the only time you're tested. Third, if you get tested early in a major tournament, you're not likely going to get tested again unless you make the finals.
Case in point: At the 2009 Australian Open Finals, Federer and Nadal were each tested once. After the finals.
I think this indicates that micro-doping during competition is quite well established.