Lindsay Whalen had surgery to repair a fracture in the fifth metacarpal of her left hand Friday at the Mayo Clinic in Rochester.
The veteran Lynx point guard broke the bone near her pinkie finger in Thursday's victory over Atlanta at Xcel Energy Center.
The team said Whalen will be sidelined indefinitely.
The usual time frame for recovery from such a surgery is three to four weeks. The regular season for the Lynx (20-2), who have already clinched a playoff spot, ends Sept. 3.
Whalen has started every Lynx game this season and is averaging 8.0 points and 4.1 assists.
Renee Montgomery will likely replace her as a starter. Montgomery tied a season high with seven assists against the Dream in 18-plus minutes. She is averaging 7.0 points and 3.0 assists.
Lynx coach Cheryl Reeve said All-Star guard Seimone Augustus will play in the team's next game at Indiana on Sunday. She missed the past two games because of personal reasons.
Kent Youngblood