Brittney Griner's Estranged Wife Claims She Needs Support to Pay Bills

Brittney Griner's estranged wife, Cherelle Griner, is asking the court to consider how rich the WNBA star is when determining support ... TMZ has learned.

Cherelle filed court docs responding to Brittney's divorce petition after 8 years of marriage. During Brittney's detention in Russia, Cherelle was extremely vocal, calling for her release.

In her paperwork, Cherelle listed the date of marriage as June 18, 2018, and the date of separation as July 24, 2026 ... and she said the marriage is "irretrievably broken with no hope for reconciliation."

Cherelle wants joint legal custody of their kid, Bash Griner, and wants the court to make a ruling on physical custody and parenting time based on the best interests of the child.

She's also asking the court to award her financial support … and pointed out Brittney earns a ton more than she does.

Brittney is playing for the WNBA's Connecticut Sun and reportedly signed a one-year contract worth over $1 million.

Cherelle said there is a "substantial disparity" in income, and she is "unable to meet her reasonable financial needs on a monthly basis without continued support."