WAYNE ROONEY ISN’T the only sports star whose hair-growth experimentation is attracting headlines.

Ryohei Yamanaka was left regretting his decision to attempt to grow a moustache with hair growth products, when he discovered the cream in question contained traces of steroids.

After his player tested positive for the substance, Japan head coach John Kirwan said he anticipated Yamanaka would be banned for at least six months – meaning his player would miss the World Cup in September.

Kirwan expressed disappointment at the incident, which looks set to affect his team’s World Cup plans.

“I spoke to him at the time. I don’t think he was aware of the severity of it. We spent 24 hours trying to find out what he had taken.

“It was a little tube of hair-growth cream. He just didn’t think. Apparently he has failed the (B sample) too. From what I gather he’s innocent but (the IRB) take a dim view.”

Yamanaka added, via Twitter, that he was “sorry for causing such problems”.

He also clarified that the substance was “not a hair growth tonic which helps grow hair on the head”.

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