INDIAN WELLS, Calif.—Alexander Zverev has denied a story in a Serbian publication saying that he is using the same banned drug for which Maria Sharapova tested positive.

Earlier this week, Sharapova announced that she had tested positive for meldonium, saying that she had been taking it for many years. The substance was banned by WADA at the beginning of this year.

A story by alo.rs quoted Germany's former Davis Cup captain Niki Pilic, who is from Serbia, saying that Zverev used the drug. Pilic was quoted describing it as a medication for diabetes.

However, Zverev denied the story, saying he had never heard of the substance before.

"I honestly never took it. I do not know where that is even coming from. I have no idea what that substance even is, and everything that has been there is absolutely not true," he said following his first-round victory at Indian Wells.

"I am getting tested with doping, you know, almost every week, so, you know, if I would be taking that substance which is not allowed, there would be bigger news than just that little article.

"Everything that is in it that is not true.”

Zverev also questioned why such comments would be issued by Pilic.

"Honestly, we don't really have a relationship. I saw him once at Davis Cup. He was in the team, but he wasn't really a lot of—he wasn't spending a lot of time with us," said Zverev.