Gino Marchetti, one of the most feared defensive ends in pro football history, who helped lead the Baltimore Colts to two consecutive National Football League championships — including a 1958 overtime victory over the New York Giants often immortalized as “the greatest game ever played” — died April 29 at a hospital in Paoli, Pa. He was 93.

His death was announced by the Baltimore Ravens. The cause was pneumonia.

Mr. Marchetti, who fought in the Battle of the Bulge during World War II and worked as a bartender before attending college in California, did not play his first professional football game until he was 26. By the time he played his final game in 1966, at 40, he had been credited with redefining the position of defensive end and became one of pro football’s first defensive superstars.

In 2010, more than 40 years after he retired, the NFL ranked Mr. Marchetti as the 39th-best player in pro football history, and the third best defensive end after Reggie White and Deacon Jones. Mr. Marchetti was named to the Pro Football Hall of Fame in 1972.

At 6-foot-4 and about 245 pounds, Mr. Marchetti was called “Gino the Giant.” He lined up as close to the line of scrimmage as he could and was extraordinarily quick off the ball. Instead of directly facing the offensive tackle, he took his stance at an angle, aimed directly at the opposing quarterback.

Mr. Marchetti wore just a small, double-bar face mask, with no pads on his arms and no tape or gloves on his hands. He was among football’s fiercest pass rushers, maneuvering past blockers and using his exceptional strength to fling them to the turf.

The sack — in which a quarterback is tackled behind the line of scrimmage before he can throw a pass — did not become an official statistic until 1982. The NFL record for sacks for a 16-game season is 22½ , set by Michael Strahan in 2001.

One year, the Baltimore coaching staff reviewed a season’s worth of game film and counted 43 sacks by Mr. Marchetti — in a 12-game season. He once had nine sacks in a single game.

Detroit Lions quarterback Bobby Layne said that being sacked by Mr. Marchetti was “like running into a tree trunk in the dark.”

An opposing player once slathered Vaseline on his uniform to prevent Mr. Marchetti from grabbing him. After a few plays, Hall of Fame quarterback Fran Tarkenton recalled in an NFL Films interview, Mr. Marchetti ripped the player’s jersey off and tore it into pieces: “He said, ‘Kid, when you come back in here the next time, don’t put any grease on your jersey.’ ”

Mr. Marchetti had been a member of the Colts since the team’s inaugural NFL season in 1953, after the remnants of a failed franchise in Dallas were rebuilt in Baltimore. During his rookie season with the short-lived Dallas Texans, Mr. Marchetti played offensive tackle.

In Baltimore, his new coach, Weeb Ewbank, switched him to defensive end. In 1954, Mr. Marchetti was named to the first of 11 Pro Bowl teams.

Quiet and unassuming off the field, Mr. Marchetti nervously smoked a cigarette in the clubhouse before leading his Colts onto the field as team captain. He had an intense, dark-eyed glare that never wavered throughout a game. He constantly paced the sideline, eager to return to action.

In 1958, the once-lowly Colts — led by young quarterback Johnny Unitas — won the NFL’s West Division with a 9-3 record. They twice played the East Division champions, the New York Giants, winning one game and losing one.

The two teams met for the NFL championship on Dec. 28, 1958, before 64,000 fans at New York’s Yankee Stadium.

“The first pass the Giants tried to throw was no good at all,” Washington Post sports columnist Shirley Povich wrote. “Gino Marchetti poured through the Giants’ protective cordon and batted the ball back into [quarterback] Don Heinrich’s face.”

Late in the fourth quarter of the game, with the Giants leading 17-14, New York’s star halfback, Frank Gifford, was running for a first down when he was stopped by Mr. Marchetti. Another Colt tackler, 285-pound Gene “Big Daddy” Lipscomb, landed on Mr. Marchetti’s right leg.

“I never hurt so bad in my life,” Mr. Marchetti told the Baltimore Sun last year. “Gifford said, ‘Okay, Marchetti, quit faking it. You can get up now.’ I told him, ‘I can’t, Frank — my ankle’s broken.’ ”

Mr. Marchetti’s tackle had prevented Gifford from making a first down by inches. He was taken off the field on a stretcher but insisted on staying on the sideline as Unitas led the Colts downfield for a game-tying field goal by Steve Myhra.

For the first time the game was decided in overtime, as Colts fullback Alan Ameche plunged across the goal line in the twilight to give Baltimore the NFL championship, 23-17.

“It was just the right climax,” Tex Maule wrote in Sports Illustrated, “for the best game of football ever played.”

Mr. Marchetti returned to Baltimore, where so many people came to his hospital room during his convalescence that a quarantine sign was put up.

“I’d wake up from a snooze and find 20 people standing around my bed,” he said last year. “Didn’t know any of them.”

Gino John Marchetti was born Jan. 2, 1926, near Smithers, W.Va., to Italian immigrants. The family soon moved to Antioch, Calif., where his father ran a tavern.

Mr. Marchetti did not play much football until his final year of high school. He left school before graduating to join the Army and served as a machine-gunner during the Battle of the Bulge in the brutally cold winter of 1944-1945.

“The first time I saw snow,” he said years later, “I slept in it.”

Back in California, Mr. Marchetti worked as a bartender before joining a semipro football team. He then played at a junior college before going to the University of San Francisco, riding onto campus on his motorcycle, wearing a black leather jacket and long, flowing hair.

His coach, Joe Kuharich — who later led the Washington Redskins — didn’t know what to make of Mr. Marchetti until he saw him play. Mr. Marchetti was captain of the 1951 San Francisco Dons, forever known as “unbeaten, untied and uninvited.”

The team was offered a chance to appear in the Orange Bowl, but one of the conditions of playing against a segregated team from Georgia Tech was that San Francisco’s black players stay behind.

Mr. Marchetti and the rest of the team refused.

While still playing for the Colts, Mr. Marchetti opened the first of what became a nationwide chain of hundreds of Gino’s hamburger franchises. He sold the company in 1982 for $48 million.

He settled in West Chester, Pa., and later entered deep-sea fishing competitions and bowling tournaments, rolling a 299 (out of 300) when he was 79.

His marriage to Flora Etta Beck ended in divorce. Survivors include his wife since 1978, the former Joan Plecenik of West Chester; five children and stepchildren; 16 grandchildren; and 14 great-grandchildren.

In 1959, a year after the “greatest game,” the Colts met the Giants again for the NFL championship, winning handily by a score of 31-16. Mr. Marchetti retired after the 1964 season but returned two years later, after the Colts became shorthanded through injury.

“I was as excited at the end of my thirteenth season as I was at the first,” Mr. Marchetti told former Post sportswriter William Gildea for the 1994 book “When the Colts Belonged to Baltimore.” “I think of coming out onto the field. I think of the band playing the fight song. I thought I was the luckiest guy in the world.”

An earlier version of this story incorrectly stated that the University of San Francisco did not field a football team after 1951. The university had a Division II team from the late 1960s to the early 1980s.