Sara L. "Sally" Buck, 83, who joined the Phillies' limited partnership that formed in 1981, died on Saturday morning.
Before Saturday's game at Citizens Bank Park against the St. Louis Cardinals, there was a moment of silence for Mrs. Buck.
"Sally was loved by many in the Phillies organization from front-office staff, to players, to fellow owners," team president David Montgomery said in a statement. "Her passing leaves the club with a profound sense of loss."
Mrs. Buck and her late husband, Alexander "Whip" Buck, became part of the Phillies ownership group in December 1981. According to the Phillies, none of the longtime partners owns as much of 50 percent of the partnership.
"As her sons, Pete and Sandy, said: 'Sally always put family and others first, ever humble and selfless, and deeply committed to her community, her friends, and those in need. She modeled love, strength, virtue, good cheer, and wisdom,' " Montgomery said.
Mrs. Buck was the second Phillies owner to die this year. Claire Betz passed away in February. The team has been wearing her initials on uniform jerseys this season.