Charles O. Finley, the contentious and colorful former owner of the Oakland A's who challenged baseball tradition by championing changes like bright-colored uniforms and the designated hitter, died yesterday at Northwestern Memorial Hospital in Chicago. He was 77.

Finley, who lived on a farm in LaPorte, Ind., died of heart and vascular disease, from which he had been suffering for years, said a hospital spokeswoman, Lauri Sanders.

From the time he bought the Athletics in 1960, when they were situated in Kansas City, Mo., to the time he sold them as a declining franchise in Oakland, Calif., after the 1980 season, Finley not only fought with everyone from commissioner to groundskeeper, but also constantly pressed for innovations in a sport that had hardly changed in a half-century.

He dabbled in other sports briefly, purchasing the Oakland Golden Seals of the National Hockey League in 1970 and the Memphis Pros (later the Tams) of the American Basketball Association in 1972. But it was in baseball that he bucked tradition.

Some of his ideas were considered silly, such as an orange-colored baseball. But others, like the designated hitter and night games in the World Series, became fixtures.

After seven woeful years in Kansas City, Finley moved the franchise to Oakland for the 1968 season and built the dominant team in the early 1970's, a thickly mustached and heavily sideburned squad that won three straight World Series from 1972-74, in spite of bickering among the owner, players and managers.

Three members of those teams -- Reggie Jackson, Catfish Hunter and Rollie Fingers -- were signed by Finley and are in the Baseball Hall of Fame. But all three, as well as many teammates, were lost by Finley after the era of free agency dawned in the mid-70's.

Recalling those championship seasons yesterday, Hunter, now a spring training instructor for the Yankees, said in a statement that Finley "was the type of owner who knew a lot about baseball and knew how to get great players and win; he was 10 to 20 years ahead of his time."

Jackson, now part of the Yankees' special advisory group, said that Finley "was a tough guy," who had taught him "a lot about demanding excellence, and that helped mold my career."

Charles Oscar Finley was born on Feb. 22, 1918, in Ensley, Ala., near Birmingham. His father and grandfather were steelworkers. At 13, he worked as a bat boy for the Birmingham minor league team. At 18, he worked in the steel mills in Gary, Ind.

He studied engineering in college at night and played considerable semipro baseball. In 1941, he married Shirley McCartney. They had seven children and eventually divorced. During World War II, he was rejected for military service because of an ulcer, went to work in an ordnance plant and started selling insurance. When the war ended, he turned to insurance full time.

But late in 1946, at the age of 28, he developed tuberculosis and spent the next 18 months in a sanitarium at Crown Point, Ind. By the time he recovered, he had devised a blueprint for a group insurance plan for doctors. By 1954, he had his own company, several million dollars and an intense desire to buy a major league baseball team.

But he did not get one until March 1960, when he bought the Kansas City Athletics, the old Connie Mack franchise that had moved from Philadelphia after the 1954 season.

His eight years in Kansas City were stormy. His promotional ideas were ingenious: the colorful green and gold uniforms, the sheep grazing on the grassy slope behind the right-field fence, the mechanical rabbit that popped up behind home plate with a supply of new baseballs for the umpire and the team mascot, a mule named Charlie O.

As he established his one-man regime, his middle initial came to stand for "owner." Every detail had to be cleared through him. He changed managers and general managers with bewildering speed, got into lawsuits with former employees, antagonized the baseball establishment.

But attendance remained low for a team that never had a winning season, and after continual threats to move, Finley packed up for Oakland.

While he made money there, the attendance was never much higher than in Kansas City. Bitter salary struggles, especially with Jackson and Vida Blue, helped solidify the image of conflict that surrounded a team so unorthodox that it even employed a track sprinter, Herb Washington, as a designated runner for the 1974 season.

Finley found a manager, Dick Williams, who finally brought his developing stars to first place (1971) and two World Series triumphs (1972 and 1973). But when Williams quit, and tried to move to the Yankees, Finley stopped him with legal action, then allowed him to become manager of the California Angels a few months later.

Williams, now an adviser to the Yankee owner George Steinbrenner, said by telephone from Tampa, Fla., yesterday: "At the time, there was friction and all that. But you forget about that. I'll remember all the innovations and that if a player got injured and I needed one, the next day I'd have two or three to choose from. He wanted to win."

In 1974, the A's won their third straight World Series, this time under Manager Alvin Dark, whom Finley had fired before. But in the course of that season, Finley failed to carry out the exact terms of his contract with Hunter, who had become baseball's best pitcher, and an arbitrator made Hunter a free agent. Hunter signed a five-year deal with the Yankees, and Finley embarked on another long lawsuit.

The fortunes of Finley began to dip in 1975 when the A's won the American League Western Division crown again, but were beaten in three straight games by Boston in the playoffs. Shortly after, Finley fired Dark as manager.

But his real problems arose with the decision of a Federal judge to uphold an arbitration ruling of Peter Seitz that opened the door for free agency in baseball.

Realizing that he might lose all of his unsigned stars at the end of the 1976 season, he traded Jackson and Ken Holtzman to Baltimore, then sold Blue to the Yankees and Joe Rudi and Fingers to the Red Sox.

But four days later, Commissioner Bowie Kuhn voided the sales and ordered the players back to the A's, saying, "The deals were inconsistent with the best interests of baseball." Finley, enraged, called the commissioner "the village idiot" and filed a damage suit, challenging whether the commissioner had the power to cancel a sale of players. He lost the case in court.

"I think Charlie will be remembered probably as a maverick," Kuhn told The Associated Press yesterday. "Charlie was Charlie. He didn't like people telling him what to do. He liked to do his thing, his own way."

Besides the court case, Finley lost most of his championship team and the A's limped along for most of the 1977 season. By 1979, when the Athletics finished 54-108, attendance was down to 306,763. After two attempts to move the franchise to Denver fell through, Finley sold the team to the Haas family for $12.7 million and dropped from the baseball scene.

Some of his innovations, however, had taken hold. Many teams wore bright uniforms. World Series games were played at night, starting in 1971. And since 1974, the American League has used a designated hitter instead of letting the pitcher bat.

Charles O Finley