Brittney Griner, the basketball star who was detained in Russia for 10 months, has signed a one-year contract to continue her playing career with the W.N.B.A.’s Phoenix Mercury, according to a person with knowledge of the agreement who spoke on condition of anonymity.

Griner became the center of a geopolitical showdown between the United States and Russia for much of 2022 after customs officials at an airport near Moscow detained her for carrying a small amount of cannabis oil in vape cartridges in her luggage.

A Russian court convicted her of drug smuggling, and in August Griner was sentenced to nine years in a penal colony. The State Department declared Griner wrongfully detained and sought a prisoner exchange for her release.

An exchange was made in December, with Griner being returned to the United States while Viktor Bout, an arms dealer who had been convicted nearly a decade earlier, was sent back to Russia.

In an Instagram post after her release, Griner pledged that she would work to free other Americans who have been declared wrongfully detained and that she planned to play in the W.N.B.A. again.

Griner last played in the W.N.B.A. in 2021, producing one of the best campaigns of her career with averages of 20.5 points, 9.5 rebounds and 1.9 blocks. Phoenix opens its season against the Los Angeles Sparks on May 19.

Tania Ganguli contributed reporting.