Andy Murray says the decision by his racket sponsor Head to show support for Maria Sharapova following her failed drugs test is "strange", adding that she should face a suspension.
Speaking at a news conference ahead of the BNP Parabas Open in Indian Wells, Murray said he disagrees with the company's decision to support Sharapova.
Head released a statement on Thursday saying it was "proud" to be associated with the five-time grand slam winner Sharapova.
The statement came three days after she revealed she had tested positive for the banned substance meldonium.
The company also said it intends to extend its contract with Sharapova.
Murray said: "I think it's a strange stance given everything that's happened in the last few days.
"I don't really know what else to say on that, but that's not something I believe.
"I think at this stage it's important really to get hold of the facts and let things play out, like more information coming out before making a decision to extend the contract like that, in my view.
"I personally wouldn't have responded like that."
Murray added that he believes Sharapova should be suspended in the wake of her failed drug test.
"It's not up to me to decide the punishment, but if you're taking performance-enhancing drugs and you fail a drugs test, you have to get suspended," he added.
Sharapova revealed during a news conference on Monday that she had been taking the drug legally for 10 years for health reasons on the advice of her family doctor.
She claimed she did not know it had been added to the World Anti-Doping Agency's list of banned substances on 1 January.