Minnesota Lynx center Sylvia Fowles suffered a right calf strain Thursday and is out indefinitely, the team announced Friday.
The Lynx said further updates will be issued when more information is available.
Fowles, 34, previously missed games on Aug. 5 and Aug. 9 because of the calf issue, but she played on Aug. 7 and Aug. 11.
The 2017 WNBA MVP and two-time WNBA champion entered Thursday's game averaging 16.7 points and 11.3 rebounds. She became the WNBA's all-time leading rebounder on July 28.
Fowles went to Minnesota in a trade from Chicago midway through the 2015 season and had not missed a game with the Lynx until this year.
"It's the type of blow you'd think it would be. You're losing one of the best players in the league and an MVP candidate," Minnesota coach Cheryl Reeve said after the game. "We did play a couple of games without Syl, so we're sort of familiar with what needs to happen and what our rotations will be."
The Lynx lost one of their other captains, forward/guard Karima Christmas-Kelly, to a season-ending Achilles injury on July 28.