The Day in Sports : COUNTDOWN TO 2000 / A day-by-day recap of some of the most important sports moments of the 20th Century: AUG. 31, 1969 : A Perfect Champion Dies in Plane Crash

Thirty years ago today, boxing lost its only perfect heavyweight champion.

Rocky Marciano was only 45 when he died, killed with two others in the crash of a small plane two miles south of Newton, Iowa.

They called him “the Rock” and “the Brockton [Mass.] Strong Boy” when, as an undersized young heavyweight, he was knocking contenders stiff in the late 1940s.

The oldest of six children, he was born Rocco Francis Marchegiano. He learned to box in the Army during World War II, when he also ferried supplies from England to the Normandy beachhead.

He boxed as an amateur after the war, and worked as a dishwasher, ditch digger, factory hand, snow shoveler and beer deliverer’s helper.

He turned pro in 1947 and in one stretch knocked out seven of eight foes in the first round. He was 42-0 when he fought champion Jersey Joe Walcott in 1952, scoring the most dramatic victory of his career. Trailing on points, he knocked Walcott out in the 13th round.

The brawling, relentless Marciano was often outweighed in his seven title fights, his top weight as champion only 189 pounds.

His 1955 defense against Archie Moore was his last fight. He was 49-0 and had won 43 fights by knockout when he announced his retirement from boxing in 1956. That surprised nearly everyone, since Marciano was reasonably close to a rich fight with young challenger Floyd Patterson.

Marciano remains boxing’s only unbeaten heavyweight champion.

Also on this date: In 1959, before 82,074 at the Coliseum, the Dodgers’ Sandy Koufax struck out 18 Giants. In a 5-2 Dodger win, Koufax fanned 15 of the last 17 hitters. . . . In 1903, for the third time in a month, the New York Giants’ “Iron Man” Joe McGinnity went the distance in both games of a doubleheader and won both. In that season, McGinnity pitched complete games in 44 of 48 starts.

In 1964, ground was broken for Anaheim Stadium. . . . In 1990, Seattle’s Ken Griffey Sr., 40, and Ken Griffey Jr., 20, become the first father-son combination to play together in major league history. Each had a first-inning single. . . . In 1950, Brooklyn’s Gil Hodges hit four home runs and a single as the Dodgers beat the Boston Braves, 19-3.