Roosevelt Brown, the Hall of Fame offensive tackle who spent the last 51 years with the Giants as a player, an assistant coach and a scout, died Wednesday at his home in Columbus, N.J. He was 71.

He apparently had a heart attack while gardening, his wife, Linda, said.

In 1953, Brown was chosen by the Giants in the 27th round of the National Football League draft as an obscure 6-foot-3, 225-pound player from Morgan State in Baltimore. He played 162 games for the Giants over 13 years. As their left offensive tackle, whose primary responsibility was to protect the quarterback, he grew to 255 pounds and was named to eight All-Pro teams and 10 Pro Bowls.

He helped coach the Giants' offensive line from 1966 to 1971, then became a scout, seeking the best offensive line prospects in college.

From 1956 to 1963, Brown's Giants teams won one N.F.L. and six division titles. Five teammates -- Frank Gifford, Sam Huff, Andy Robustelli, Y. A. Tittle and Emlen Tunnell -- were also elected to the Pro Football Hall of Fame. Brown was elected in 1975, and in 2000 he was named to the N.F.L.'s 75th anniversary team.

When his pro career started with the 1953 draft, there were 30 rounds, as opposed to seven now. Brown was the 318th player chosen. As Dave Anderson wrote in 1975 in The New York Times:

''At the time, scouting was not even organized, let alone computerized. The extent of some teams' search was the various all-America teams. Someone in the Giants' delegation noticed the black all-America selected by The Pittsburgh Courier, a black weekly newspaper.''

Brown was on that team. The Giants drafted him and signed him to a one-year contract for $3,000 (no signing bonus) and a train ticket to training camp. He left for camp with a cardboard suitcase, a homburg, an umbrella and a box lunch.

Years later, he said: ''I thought that if they drafted you, they kept you. I really didn't know you could get cut.''

Al DeRogatis, a Giants lineman, scout and camp coach, once said, ''He didn't even know how to take a proper stance.'' Brown learned the hard way.

Ernie Accorsi, the Giants' general manager, said Brown once told him this: ''I was playing against Len Ford of the Browns and I couldn't block him. He would jump over me. Steve Owen was the head coach then, and he said if you can't block him, we're going to cut you. So I tackled Ford two straight plays. He said, 'If you do that again, I'm going to kill you.' I said, 'Well, if I don't stop you, I'm going to get cut, so what's the difference if you kill me?' ''

Brown's teammates spoke yesterday about his unusual skills.

''I wouldn't be in the Hall of Fame if it weren't for him,'' Gifford said. ''The longest run of my career was on a pitchout against Washington,'' Gifford said, referring to a 79-yard gain. ''Rosie made a block at the line of scrimmage. I cut it up, and then I'm running downfield and I look up and I see No. 79 in front of me, and he wiped out another guy.''

Huff said their first meeting came when Brown, in T-shirt and shorts, was sitting outside the dormitory in training camp.

''He was a big Jim Brown,'' Huff said, referring to the Cleveland Browns' star fullback. ''I wanted to turn around and go back to West Virginia. I said, 'Are they all built like this?' ''

Roosevelt Brown was born Oct. 20, 1932, in Charlottesville, Va. He played the trombone in his high school band until the football coach, seeing a 13-year-old who weighed 180 pounds, made him a player. He went on to earn a football scholarship and a degree from Morgan State.

He succeeded in every job with the Giants. Accorsi remembered this moment years ago in the draft room:

''Rosie gave a spontaneous philosophical talk. If it was recorded, it would be a manuscript for how to conduct a draft, a manuscript on scouting, on how to get these kids to become a finished product. He was a very wise man.''

Brown is survived by his wife, the former Linda Lock; a stepson, Kyle Anglin of Montclair, N.J.; a stepdaughter, Tiffany Anglin of Petersburg, Va.; three stepgrandchildren; and two sisters, Lyria Hailstork and Mary Page, both of Charlottesville.

In his prime, Brown earned $20,000 a year.

''Nobody plays this game for the money,'' he said then. ''You have to enjoy it. You have to have the game in your heart. They can't pay us enough for what we go through on the field.''

Photo: Roosevelt Brown in 1964, his next-to-last season with the Giants. After his playing career, he was an assistant coach, then a scout for the team. (Photo by The New York Times)