Thomas was designated as the team’s franchise player earlier this month, meaning the only way she could sign with another team was via trade. The move can't become official until Feb. 1.

The Sun gave Thomas the core designation earlier in January, meaning the only way for Thomas to be moved was via a sign-and-trade

The Connecticut Sun traded Thomas to the Phoenix Mercury on Tuesday, according to ESPN’s Alexa Philippou. It’s unclear what the Sun will get in return. Thomas was originally drafted by the New York Liberty in 2014 but was traded on draft day to Connecticut and will leave the team as one of its greatest players in franchise history.