The Oct. 26 obituary of Wellington Mara incorrectly stated that the New York Giants played the Washington Redskins in a football game Dec. 7, 1941. The Giants lost to the Brooklyn Dodgers that day, 21-7. (Published 10/27/2005)

Wellington Mara, who had owned the New York Giants football team since 1930 and was a primary architect in making professional football the dominant team sport in the United States, died Oct. 25 of lymphatic cancer at his home in Rye, N.Y. He was 89.

Mr. Mara never played football, yet his longevity in the sport gave him an unrivaled authority. Perhaps the last living link to the earliest days of the National Football League, he had been associated with the Giants since his father bought the team for $500 in 1925. Then 9 years old, Mr. Mara fetched pails of water and polished players' shoes.

In 1930, when he was only 14, he became a half-owner of the Giants when his father transferred the team to him and his 22-year-old brother, Jack. Over the next 75 years, Mr. Mara attended nearly every game and most of his team's practices. He maintained control of the Giants, one of the league's most successful franchises, until his death.

He was part of the NFL's first generation of owners, which included George Halas of the Chicago Bears, Earl "Curly" Lambeau of the Green Bay Packers and Art Rooney of the Pittsburgh Steelers. Together, they transformed professional football from a disreputable sideshow spectacle to an immensely profitable game that has become a Sunday afternoon ritual.

As closely as he followed the fortunes of his team, Mr. Mara had a vision broad enough to ensure the strength of the league as a whole. In 1970, he helped engineer the merger of the NFL and the younger American Football League.

In 1961, Mr. Mara was instrumental in creating revenue sharing, in which all teams split profits from television networks. The resulting financial stability and closer competition ultimately helped establish pro football as America's most popular sport.

In 1997, he was named to the Pro Football Hall of Fame.

"When Well Mara stood to speak at a league meeting, the room would become silent with anticipation because all of us knew we were going to hear profound insights born of eight decades of league experience," NFL Commissioner Paul Tagliabue said in a statement yesterday.

Mr. Mara was a quiet, dignified man who seldom interfered in his coaches' decisions. Win or lose, he greeted his players in the locker room with handshake and, after their careers had ended, often helped them in business or with personal problems.

"How lucky was I to have Mr. Mara?" former Giants quarterback Phil Simms told The Washington Post in 2001. "He's loyal, he's true and he only demands a few things: be responsible, show up every day and work hard."

Wellington T. Mara was born Aug. 14, 1916, in New York. He was christened Timothy Wellington Mara, but the order of his names was reversed in official records. He was sometimes known by his nickname, Duke.

His father, a legal bookmaker, bought the fledgling New York Giants when the NFL was struggling for a legitimate place in the sports landscape.

Mr. Mara attended his first Giants game Oct. 18, 1925, when they lost to the Frankford (Pa.) Yellow Jackets, 14-0. Among the Giants players was the legendary multisport athlete Jim Thorpe.

After Mr. Mara came home with a cold from standing in the autumn shade, his mother demanded that the team's bench be moved to the sunny side of the field. Since then, the Giants have kept their bench in the sun, opposite the press box. In the 1970s, Coach Bill Arnsparger complained to Mr. Mara that opposing teams used the press box to steal the Giants' signals.

"Get better signals," Mr. Mara told him.

Although he was a nominal owner at 14, Mr. Mara formally assumed a front-office job with the Giants in 1937, when he graduated from Fordham University.

Mr. Mara learned of the Japanese attack on Pearl Harbor while at a game between the Giants and the Washington Redskins. During World War II, he served three years as a Navy officer. After the Sept. 11, 2001, attacks, he joined his players on a bus tour of New York fire and police stations.

In the 1950s, Mr. Mara assembled a Giants team that included such stars as quarterbacks Charley Conerly and Y.A. Tittle, halfback Frank Gifford, linebacker Sam Huff and linemen Andy Robustelli and Roosevelt Brown Jr. He hired two assistant coaches, Vince Lombardi and Tom Landry, who later had Hall of Fame careers.

The Giants won the NFL championship in 1956 and played in five other championship games in the next seven years, including an overtime loss to the Baltimore Colts on Dec. 28, 1958, that is widely known as "the greatest game ever played."

The reserved Mr. Mara could be a hard-nosed negotiator, as Huff learned in 1956 when he asked for an increase of his $7,500 salary. Mr. Mara announced he would give him a raise of $500.

Insulted by the paltry offer, Huff repeated "$500" in a scoffing tone.

"Sam," Mr. Mara responded, "I think you're worth it."

The team endured a period of decline until 1979, when Mr. Mara's nephew, Tim Mara, insisted on hiring a new general manager and coach. The two men were scarcely on speaking terms, but the Giants rebounded to win the Super Bowl in 1987 and 1991. Under Mr. Mara's ownership, the Giants won 18 divisional titles and six NFL championships.

In 1999, after the Giants suffered two embarrassing losses in a row, Mr. Mara addressed the team for the first time in 30 years.

"I guess basically my message was shape up or ship out," he said.

Even then, the players removed their hats in respect.

Survivors include his wife of 51 years, Ann Mumm Mara; 11 children; and 40 grandchildren.

On Oct. 23, as an ailing Mr. Mara rested at home, the Giants defeated the Denver Broncos, 24-23, by staging a last-minute rally. After the game, the players gathered in a circle, chanting Mr. Mara's nickname, "Duke, Duke, Duke!"

Mr. Mara's family said he woke up to watch the winning play on television, smiled, then went back to sleep.

Wellington Mara, owner of the New York Giants since 1930, with his bronze bust at his induction in 1997 to the Pro Football Hall of Fame.