Griner was detained at an airport in February after Russian authorities said a search of her bag revealed vape cartridges containing oil derived from cannabis. Since then, U.S. officials had stopped short of classifying the Phoenix Mercury player as wrongfully detained and said instead that their focus was on ensuring that she had access in jail to American consular affairs officials.
Now, though, U.S. officials have shifted supervision of her case to a State Department section - the Office of the Special Presidential Envoy for Hostage Affairs - that is focused on negotiating for the release of hostages and other Americans classified as being wrongfully detained in other countries.
"Brittney has been detained for 75 days and our expectation is that the White House do whatever is necessary to bring her home," said Griner's agent, Lindsay Kagawa Colas.
The president of the WNBA players' union, Nneka Ogwumike, noted in a separate statement that "it has been 75 days that our friend, teammate, sister, Brittney Griner, has been wrongfully detained in Russia."
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"It is time for her to come home," Ogwumike added. "Having learned that the U.S. government has now determined that BG is being wrongfully detained we are hopeful that their efforts will be significant, swift and successful."
It was unclear what prompted the shift in approach to Griner's case, though President Joe Biden's administration had been under pressure from members of Congress and others to make her release a priority.
The U.S. last week secured the release of Marine veteran Trevor Reed as part of a prisoner swap that also resulted in a convicted Russian drug trafficker being freed from prison in the U.S.
Besides Griner, another American regarded as unjustly detained in Russia is Paul Whelan, a corporate security executive from Michigan who was arrested in December 2018 while visiting for a friend's wedding and was later sentenced to 16 years in prison on espionage-related charges his family says are bogus.
ESPN first reported the classification in Griner's case. Two U.S. officials confirmed it on the condition of anonymity because they were not authorized to discuss it by name.
Meanwhile, the WNBA announced Tuesday that it would honor Griner with a floor decal and allow the Mercury to pay her without it counting against the team's cap. The decal will feature Griner's initials, BG, as well as her No. 42.
All 12 teams will have the decal on their home courts starting with the season opener Friday night. The Mercury open their season at home that night against the Las Vegas Aces.