Larry Grantham

Larry Grantham, an undersize linebacker who as the defensive captain of the Jets helped the team upset the Baltimore Colts in Super Bowl III, a watershed game in the history of professional football, died on Saturday in Jackson, Miss. He was 78.

His son, James Larry Grantham II, said the cause was complications of chronic obstructive pulmonary disease.

In his 13 seasons, from 1960 to 1972, with the Jets and their predecessors, the New York Titans, Grantham was believed to be the lightest linebacker in either the American or National Football League. Outside linebackers are now commonly about 6 feet 4 inches and 250 pounds. Record books list Grantham as 6-0 and 204 to 210, but he said he never weighed that much.

“The most I ever played at was 192, by late in the season probably 185,” he told Dave Anderson of The New York Times in 2008.

“If Larry Grantham were judged only on his size, no coach in his right mind would pick anyone so small as a linebacker,” Weeb Ewbank, the Jets’ coach from 1963 to 1973, told Arthur Daley of The Times in 1966. “But once that coach saw Larry in a game, he’d grab him in a hurry because he has such quickness, such instinctive reactions and such an acutely developed sense of anticipation that he ranks with the very best.”

In an era before offensive and defensive plays and formations were signaled in from the bench, Grantham called all the Jets’ defensive formations on the field. In the 1969 Super Bowl, when the Jets of the upstart A.F.L. upset the heavily favored Baltimore Colts of the established N.F.L., 16-7, he was at his best.

“Larry knew what everybody on defense was supposed to do on every play,” said Paul Rochester, a defensive tackle for the Jets in that Super Bowl. “The Colts kept running at me and Gerry Philbin, so Larry kept calling the same defense. ‘They’re coming your way,’ he’d yell. ‘Just keep stopping ’em.’”

The Jets’ defense held the Colts’ vaunted running game to one touchdown and shut down their passing game with four interceptions. The victory came as no surprise to the Jets, who viewed the Colts as inept after watching films of their earlier games. The week before the Super Bowl, Joe Namath, the Jets’ brash quarterback, guaranteed in public comments that his team would win. Ewbank was aghast at Namath’s brazenness, fearing it would ignite a fire under the perhaps overconfident Colts.

The Jets’ Super Bowl victory gave credibility to the young A.F.L. just before its merger with the N.F.L. in 1970. Grantham, one of 20 people who played in all 10 seasons of the A.F.L., was an A.F.L. All-Star eight times and was chosen for the second team in voting for the all-time A.F.L. team.

James Larry Grantham was born on Sept. 16, 1938, in Crystal Springs, Miss., to Carl and Mable Grantham. He lettered in football, baseball and basketball at Crystal Springs High School; on the football team, he mostly played tight end and defensive end. As a senior at the University of Mississippi, he helped the Rebels shut out Louisiana State University, 21-0, in the Sugar Bowl on Jan. 1, 1960.

He was drafted by the Colts in the 15th round of the 1960 N.F.L. draft, but he turned them down to play for the Titans of the newly formed A.F.L. “I felt it was wiser for me to pick the new league,” he told The Times in 1966, “because everyone in it would be as green as I was.”

He started his career with the Titans as a wide receiver, but two days into training camp he was moved to linebacker. He was delighted by the switch, he said years later, because “I found out I loved to hit people.”

He also loved to snatch the ball. In his first season with the Titans, he had five interceptions and three fumble recoveries.

His first three seasons with the Titans were memorable for the wrong reasons.

“We played before 3,000 people at the Polo Grounds,” he told The Times in 1967, “and you couldn’t hardly find the score in the paper the next day. When I went home, people would say, ‘Where you been, Canada?’”

After his football career ended, Grantham was a banker and a manufacturer’s representative. In February 2009, when medical bills from throat cancer and hernia surgery became overwhelming, he put his Super Bowl ring up for auction online. With 12 hours remaining, the bidding had reached more than $17,000.

Then Victor Moreno, the president of the auction house, learned that over the years Grantham had raised $1.3 million for Freedom House, a nonprofit substance-abuse center in Hunterdon County, N.J. Freedom House was raising money from other donors to buy the ring back for Grantham. Touched by the story, he returned the ring to Grantham, and Freedom House gave Grantham the money it raised.

Grantham’s first marriage, to the former Linda Hemphill, ended in divorce. He lived in Brandon, Miss., with his second wife, the former Peggy Carlin.

In addition to his wife and son, he is survived by a brother, Carey; three sisters, Charlene Ainesworth, Anne Greer and Jean Lingle; a daughter, LeAnne Williams; a stepson, Josh White; a stepdaughter, Anna Robbins; eight grandchildren; and two great-grandchildren.

Grantham’s proudest memories were his contributions to the growth and acceptance of the A.F.L. He told The Star-Ledger of Newark in 2009:

“We didn’t make the big money they’re making now, which is O.K. We built something that was really great. We were on the ground floor.”