The American basketball community decried Women's NBA star Brittney Griner's drugs conviction and nine-year prison sentence from a Russian court as "unjustified" on Thursday and called on the US government to bring her home.

"Today's verdict and sentencing is unjustified and unfortunate, but not unexpected and Brittney Griner remains wrongfully detained," said WNBA commissioner Cathy Engelbert and NBA commissioner Adam Silver in a joint statement.

"The WNBA and NBA's commitment to her safe return has not wavered and it is our hope that we are near the end of this process of finally bringing BG home to the United States."

Griner's WNBA team the Phoenix Mercury called her conviction a grave step in the two-time Olympic champion's "nightmare" detention.

"While we know it was never the legal process that was going to bring our friend home, today's verdict is a sobering milestone in the 168-day nightmare being endured by our sister, BG," the Mercury said in a statement, using a nickname for Griner.

While Griner stars for the Mercury, like many WNBA players, she competes in an overseas league as well.

Griner was returning to her Russian team, UMMC Ekaterinburg, from the United States when she was detained in February, charged with bringing cannabis vape cartridges into Russia.

"We remain heartbroken for her, as we have every day for six months," the Mercury said, while voicing faith the administration of US President Joe Biden "will do what it takes to end her wrongful detention."

"We will not allow her to be forgotten," the club said. "We are BG."

'We Are BG 42' is displayed on the exterior of Footprint Center before a WNBA game between the Phoenix Mercury and Minnesota Lynx in June
'We Are BG 42' is displayed on the exterior of Footprint Center before a WNBA game between the Phoenix Mercury and Minnesota Lynx in June GETTY IMAGES NORTH AMERICA via AFP / Christian Petersen

Minnesota Lynx coach Cheryl Reeve said players on the WNBA team who have been "glued" to Griner's trial were hit hard by the verdict.

"(The players) are all affected by it," Reeve told the Minneapolis Star Tribune. "They're having a hard time with it."

In the wake of the verdict, Biden reiterated that the United States considers Griner's detention wrongful and vowed to "pursue every possible avenue" to repatriate her.

US Secretary of State Antony Blinken said last week that Washington had made a "substantial proposal" to Moscow to free Griner and former US Marine Paul Whelan, who was imprisoned in Russia on espionage charges.

White House spokeswoman Karine Jean-Pierre said after the verdict the adminstration had again urged Russia to accept the offer.

Griner's agent, Lindsay Colas, said on Twitter that the sentence "goes to prove what we have known all along, that Brittney is being used as a political pawn."

She praised the efforts of Biden and Blinken "to get a deal done swiftly to bring Brittney, Paul and all Americans home."

Terri Carmichael, executive director of the WNBA players' union the WNBPA, also urged Blinken to keep the process moving.

"Whatever conversations Secretary Blinken and his Russian counterpart need to have, we trust that they are having them with all deliberate speed," she said.