Maria Sharapova's admission that she had been caught using a banned drug is stunning in itself. Though her tennis game has been struggling for several years now, she had parlayed her sports career and glamour into a highly successful business, rising to be the highest paid female athlete in the world. Now she faces suspension from competition, and already major sponsors have suspended their deals with her. The news is a stark reminder of how pervasive doping has become at the highest levels of professional sport.

Sharapova, 28, acknowledged that she had tested positive for the recently banned drug meldonium at the Australian Open in January. She claimed that she had been using the drug since 2006 for a variety of medical conditions and that she somehow had missed the notification from the World Anti-Doping Agency that it had been added to the prohibited list as of Jan 1. It's not a particularly convincing story, since meldonium is not approved for use in the U.S. or most of Europe.

The World Anti-Doping Agency banned the drug because it helps athletes by delivering more oxygen to muscles. Several athletes have been suspended this year after testing positive for it, including two long-distance runners, two biathletes, a cyclist and an ice dancer. And a documentary by Hans-Joachim Seppelt, the German journalist who disclosed systematic doping among Russian athletes, referred to a 2015 study in which 17 percent of Russian athletes tested were found to have meldonium in their system.

In the end, it's up to the International Tennis Federation to decide how long to suspend Sharapova. At least she did not deny the finding, saying at a news conference on Monday: "I have to take full responsibility because it's my body and it's what I put into my body and I can't blame anyone but myself."

Sharapova's case shows that major sports federations, the World Anti-Doping Agency and sponsors are becoming serious about combating doping. But, ultimately, it is the athletes who need to realize that doping is a deal with the devil — and that the price is destroyed reputations, annulled records, lost sponsorships and a disenchanted public.

FROM AN EDITORIAL IN THE NEW YORK TIMES