Doc Blanchard, the Heisman Trophy winner and three-time all-American who teamed with Glenn Davis on the unbeaten Army teams of the mid-1940s in college football’s most storied backfield pairing, died Sunday at his home in Bulverde, Tex. He was 84.

The cause was pneumonia, his daughter Mary Blanchard said.

In the 1920s, Notre Dame’s Four Horsemen captured the imagination of college football fans. A generation later, the sports headlines told of Mr. Inside and Mr. Outside — Blanchard the hard-driving fullback and Davis the speedy halfback.

Blanchard and Davis were also known as the Touchdown Twins, Blanchard scoring 38 touchdowns in three seasons (1944 to ’46) and Davis 59 in four seasons (1943 to ’46).Time and Life magazines pictured them together on their covers.

Blanchard’s best season was 1945, when he became the first junior to win the Heisman, awarded to the nation’s best college football player, and the first football player to win the Sullivan Award as the country’s top amateur athlete. He averaged 7.1 yards a carry, running for 718 yards, and scored 19 touchdowns as the Cadets went 9-0.

Blanchard also punted and kicked off, and played linebacker on defense. In the off-season, he was an outstanding shot-putter and sprinter.

“Doc Blanchard was the best-built athlete I ever saw,” the Army coach Red Blaik, who assembled a host of brilliant football players during World War II, recalled in his memoir “You Have to Pay the Price,” written with Tim Cohane. “Six feet and 208 pounds at his peak, not a suspicion of fat on him, with slim waist, Atlas shoulders, colossal legs.”

West Point announced earlier this month that it would retire the No. 35 worn by Blanchard along with the No. 61 of his former teammate Joe Steffy, a star guard, at ceremonies this fall. It previously retired the No. 41 worn by Davis and the No. 24 of the 1958 Heisman-winning running back Pete Dawkins.

Steffy marveled at Blanchard’s versatility, notwithstanding his Mr. Inside nickname.

“One of his favorite plays was running right up the middle, and he would go over me,” Steffy said in an interview Monday. But he also remembered how Blanchard “could run around end almost as good as Glenn Davis.”

Felix Anthony Blanchard Jr. grew up in Bishopville, S.C., the son of a country physician who had played fullback at Tulane. He was given a toy football by his father, who was known as Doc, and was soon called Little Doc. In 1942, he starred at fullback for theUniversity of North Carolina freshman team.

Blanchard entered the Army in 1943 and was stationed in New Mexico with a chemical-warfare unit when he was recruited by West Point. When his father died shortly before he entered the academy, he dropped the Little from his nickname.

In 1944, his first season, Blanchard finished third in the Heisman voting, behind Ohio State’s Les Horvath, the winner, and Davis.

While Blanchard would bust up the middle, Davis was outrunning defenders down the sidelines, inspiring George Trevor, a sportswriter for The New York Sun, to call them Mr. Inside and Mr. Outside.

“I was strong in the legs,” Blanchard said in an interview for “After the Glory: Heismen,” by Dave Newhouse. “I had good acceleration for my size, good quickness. But I wasn’t what you would call a speed guy, like Glenn.”

Army went 27-0-1 with Blanchard and Davis in the backfield together from 1944 to 1946. A perfect record over that period was spoiled by a 0-0 tie with Notre Dame at Yankee Stadium in November 1946.

Blanchard was a first-round draft pick of the Pittsburgh Steelers. In 1947, shortly after their graduation from West Point, Blanchard, Davis (also a three-time all-American and the Heisman winner in 1946) and Army end Barney Poole sought four-month furloughs from military service in order to play in the N.F.L. Some Congressmen said the players were seeking special privileges, and the War Department turned down the request.

Blanchard and Davis did team up again, playing themselves in “The Spirit of West Point,” a movie filmed in the summer of 1947. Blanchard coached Army’s freshman team in the 1950s, but he never played professional football, choosing an Air Force career instead. Davis played two years for the Los Angeles Rams after serving in the infantry.

Blanchard became a fighter pilot, and in 1959 was back in the news. While flying back to his base near London, an oil line in his plane ruptured and fire broke out. Blanchard could have parachuted, but the plane might have crashed into a village. Instead, he stayed with the craft and made a perfect landing, an action that brought an Air Force commendation.

In the Vietnam war, he flew 84 missions over North Vietnam, piloting a fighter-bomber during a one-year tour of duty that ended in January 1969. He retired from the Air Force in 1971 as a colonel.

In addition to his daughter Mary, with whom he lived in retirement, Blanchard is survived by his daughter Jo Mills, of the San Antonio area; his son, Felix Blanchard III, of North Carolina; a sister, Mary Elizabeth Blanchard, of Sumter, S.C.; and seven grandchildren. His wife, Jody, died in the early 1990s.

Davis died at 80 in 2005.

In 1984 Blanchard was on hand at the Downtown Athletic Club in Manhattan for the awards ceremony marking the 50th Heisman presentation. By then, the hoopla surrounding the trophy was huge, and the winner’s name was announced on national television.

Blanchard took the occasion to recall how he learned of his Heisman selection in 1945. “I got a telegram,” he said. “It said, ‘You’ve been selected to win the Heisman Trophy. Please wire collect.’ ”