The International Tennis Federation (ITF) says it has banned a Ukrainian doctor from sports for four years for administering a banned substance to a tennis player.
The ITF said on June 13 that Elena Dorofeyeva gave a supplement containing the stimulant dimethylbutylamine to WTA Tour player Kateryna Kozlova in 2014.
Kozlova, 22, tested positive and served a six-month ban last year.
She is the current world No. 98.