WNBA star Brittney Griner is scheduled for a trial starting Friday on charges of illegal cannabis possession in Moscow, a Russian court determined on Monday.

At a brief hearing at which Griner appeared more than four months after her airport arrest, the Phoenix Mercury player was informed of a possible sentence of up to 10 years. The maximum sentence applies to “large-scale transportation of drugs”.

During the hearing, Griner’s detention was extended by at least six months.

Griner was at the airport to board a flight back to Phoenix at the outset of the WNBA training camp. She, like other WNBA players, has spent several off-seasons playing professionally in Russia because of the higher salaries.

Court cases in communist Russia are unlike those in the United States judicial system for several reasons. The chances of conviction at any trial are higher than 95 per cent. If acquitted, the government has the authority to overturn any decision and send Griner to prison.

Griner, 31, was arrested at Sheremetyevo Airport only days before Russia sent troops into Ukraine. She was allegedly in possession of multiple cannabis oil cartridges.

Relations with the United States and Russia are tumultuous, and president Joe Biden’s press secretary said last month the tension with the Kremlin presents challenges in any attempt to negotiate Griner’s release.

"I have got no higher priority than making sure that Americans who are being illegally detained in one way or another around the world come home," U.S. Secretary of State Anthony Blinken said Sunday in a televised interview. "I can't comment in any detail on what we're doing, except to say this is an absolute priority."

The WNBA announced Griner would be a ceremonial All-Star in 2022.

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