The cause was heart failure, his daughter Erin said, adding that he had a heart attack on Oct. 5.
Known for solid shooting, mistake-free ball-handling and sticky defense, Siegfried played for the from 1963 to 1970, a period that encompassed the end of a Celtic dynasty that, beginning in 1957, accounted for 11 championships in 13 seasons. Siegfried played on five championship teams: 1963-64, 1964-65, 1965-66, 1967-68 and 1968-69.
Often overshadowed by his teammates, who included some of the most illustrious names in basketball history — Hall of Famers like Bill Russell, K. C. Jones, Sam Jones and John Havlicek, who had also been his teammate at — Siegfried was nonetheless a key element in a relentless and indomitable Celtic machine. Sometimes starting, sometimes coming off the bench, he averaged in double figures for five consecutive seasons and twice led the N.B.A. in free-throw percentage.
Siegfried traveled an up-and-down path to the N.B.A. He was born Lawrence Eugene Siegfried in Shelby, in north central Ohio, on May 22, 1939. His father was a farmer and worked for a printing company. A schoolboy legend at Shelby High, Siegfried led the state in scoring as a senior, averaging 38 points per game, then went to Ohio State. Lee Caryer, the author of “The Golden Age of Ohio State Basketball: 1960-1971,” said in an e-mail on Friday that Siegfried was “the best guard in school history.”
After leading the team in scoring as a sophomore, he was joined in his junior year by two younger players, Havlicek and another future N.B.A. great, Jerry Lucas. Siegfried then became more of a playmaker, running the team on the floor and leading Ohio State to the 1960 national championship.
“He was as good a player at guard as I’ve seen in the Big Ten,” , the celebrated college coach who played on the 1960 championship team, said in Mr. Caryer’s book, published in 1991.
The following season, after a winning streak of 32 consecutive games, Ohio State lost in the national championship game to the . It was a loss so devastating to Siegfried that when the Cincinnati Royals of the N.B.A. drafted him, he refused to sign with them, not wanting to play in that city.
Instead, he signed and played with the Cleveland Pipers, a franchise (owned by ) in the short-lived American Basketball League. In 1962, Siegfried tried out for the St. Louis Hawks, the N.B.A team that had acquired his rights, but he didn’t make it, and he spent a year teaching high school. It was Havlicek, his former Ohio State teammate, who persuaded Coach Red Auerbach to give Siegfried a tryout. After leaving the Celtics, he played for the San Diego (and the Houston Rockets, after the team moved) and the Atlanta Hawks. He retired as a player in 1972 and spent a year as an assistant coach at Ohio State and three more as an assistant with the Rockets of the N.B.A. In recent years, he counseled prisoners and worked as a motivational speaker.
In addition to his daughter Erin, of Westlake, Ohio, Siegfried is survived by his mother, Barbara; two sisters, Bonnie Slone, of Shelby, and Linda Fagg, of Willard, Ohio; his wife, the former Tina Caskin, whom he married in 1972; two other daughters, Carie Muhlenkamp, of Dublin, Ohio, and Olivia Siegfried, of Columbus, Ohio; and a grandchild.
This article has been revised to reflect the following correction:
Correction: October 19, 2010
An obituary on Saturday about Larry Siegfried misstated the years that Siegfried played for the Boston Celtics while Red Auerbach was the coach. He played under Auerbach from 1963 to 1966, when Auerbach stepped down. He did not play under Auerbach from 1963 to 1970. (He played for Bill Russell from 1966 to 1969 and for Tom Heinsohn in the 1969-70 season.)