The World Anti-Doping Agency (WADA) has revealed there have been 99 positive tests for meldonium since it was placed on their banned substances list.
On Monday, tennis and the wider sporting world was shocked by Maria Sharapova's revelation she tested positive for the drug - which was placed on the prohibited substances list at the start of 2016 - at the Australian Open in January.
Five-time grand-slam champion Sharapova said she had been taking the drug for health reasons since 2006 and was not aware of its placement on the list of banned substances.
Men's world number two Andy Murray has questioned Sharapova's reasoning for taking meldonium.
Meanwhile, Head - which sponsors both Sharapova and Murray - has come out in support of the Russian, offering her a new contract and criticising WADA's decision to ban meldonium.
Posting on Twitter, WADA spokesman Ben Nichols wrote: "Number of Meldonium positive (AAF) samples today at 99 since substance was banned on 1 January 2016."