Nike has suspended its relationship with Maria Sharapova following the five-time grand-slam champion's failed drugs test at the Australian Open earlier this year.
Former world number one Sharapova revealed on Monday that she tested positive for Meldonium at the season's opening major in Melbourne in January.
Sharapova had been taking Meldonium for a decade due to health reasons and said she was not aware it was added to the World Anti-Doping Agency's (WADA) list of prohibited substances as of January 1 this year.
And Nike wasted little time responding to the situation, releasing a statement which read: "We are saddened and surprised by the news about Maria Sharapova.
"We have decided to suspend our relationship with Maria while the investigation continues. We will continue to monitor the situation."
Sharapova - who lost to Serena Williams in the quarter-finals at Melbourne Park - will be provisionally suspended with effect from March 12, the International Tennis Federation (ITF) said.
The 28-year-old had already withdrawn from this week's BNP Paribas Open at Indian Wells due to a left forearm injury, which has proved troublesome.