As Jannik Sinner and Iga Swiatek prepare for the new season after a year in which they fell foul of doping rules, positive drug tests due to contamination are a genuine fear for many of their fellow professionals.
The star duo spent small fortunes on quickly proving how the banned substances had entered their systems but other players, many of whom do not have huge financial resources at their disposal, are understandably jittery.
"A lot of the players I know are quite apprehensive," former U.S. Open champion Emma Raducanu told British media this month.
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