Alexander Boykov said on Friday that he thinks the relatively short extension indicated that Griner's case would go to trial soon.

The 31-year-old American athlete has been in custody for nearly three months.

Griner, a two-time Olympic gold medallist who plays for the Phoenix Mercury, was detained at a Moscow airport in February.

Vape cartridges containing oil derived from cannabis were allegedly found in her luggage. She faces drug smuggling charges that carry a maximum penalty of 10 years in prison.

Griner appeared for the brief hearing at a court outside Moscow. She was handcuffed, wearing an orange hoodie and holding her face down.

She did not express "any complaints about the detention conditions", Boykov said.

The Biden administration says Griner is being wrongfully detained. The WNBA and US officials have worked toward her release but without visible progress.

"Today's news on Brittney Griner was not unexpected, and the WNBA continues to work with the US government to get BG home safely and as soon as possible," the basketball league said in a statement.

Russian officials have described Griner's case as a criminal offence without making any political associations. But Moscow's war in Ukraine has brought US-Russia relations to the lowest level since the Cold War.

The Russians may consider Griner someone who could figure in a prisoner exchange.

The State Department last week said it now regards Griner as wrongfully detained, a change in classification that suggests the US government will be more active in trying to secure her release.

Australian Associated Press