US Open semi-finalist Yanina Wickmayer has been suspended for 12 months by anti-doping officials in Belgium.
Wickmayer's fellow Belgian Xavier Malisse has also received a year-long ban from the Flemish Regional Tribunal for failure to meet World Anti-Doping Agency requirements.
Wickmayer failed to declare her whereabouts on three occasions, while Malisse had failed to do so twice and had also missed a test.
The suspensions mean Wickmayer, the world No.18, has been forced to pull out the Commonwealth Bank Tournament of Champions in Bali, while Malisse has also had to withdraw from the AXA Masters in Antwerp.
Malisse, a former Wimbledon semi-finalist, had only recently broken back into the world's top-100 after a slump in form.
The 20-year-old Wickmayer, though, has already announced her intention to appeal to the Court of Arbitration for Sport.
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