Rosenbluth was born in the Bronx in New York city, and is Jewish. He attended James Monroe High School in the Bronx, and Staunton Military Academy in Staunton, Virginia for the 1952-53 school year. He played only eight games in high school. In his first year of varsity basketball at the University of North Carolina at Chapel Hill in 1955, the 6’ 5" small forward was the Tar Heels' leading scorer. He was named third team All-America, averaging 25.5 ppg and 11.7 rebounds. In 1956 he also achieved All-America honors, but this time they were split between various first and second team selections. He again led the Tar Heels in scoring with a 26.7 average. In his senior season in 1957 Rosenbluth averaged 27.9 points and 8.6 rebounds per game while leading the Tar Heels to a 32–0 record. His regular season performance earned him the Helms Hall of Fame "Collegiate Player of the Year" designation over the University of Kansas's Wilt Chamberlain. Tar Heels went on to defeat Chamberlain's Jayhawks 54–53 in triple overtime for the NCAA Basketball Championship, North Carolina's first, which brought credibility to the fledgling Atlantic Coast Conference. Rosenbluth's scored 20 points in the championship final, was the tournament's overall top scorer at 28.0 ppg, and was named to the All-Tournament Team. He was also named the ACCPlayer of the Year and ACC Male Athlete of the Year. Rosenbluth has been honored for his athletic achievements while at North Carolina. In 2002, he was named to the ACC 50th Anniversary men's basketball team as one of the 50 greatest players in Atlantic Coast Conference history. He was selected to the "All-Decade Final Four" team for the 1950s. He is in the Helms College Basketball Hall of Fame, is listed by some as one of the "100 Greatest College Players of All-Time", and is a member of the International Jewish Sports Hall of Fame.
Other honors
Rosenbluth also received a number of other accolades and awards during his playing career:
Until Duke University's Christian Laettner, Rosenbluth was the only collegian to be named NCAA National Player of the Year, ACC Player of the Year, ACC Tournament MVP, and NCAA regional MVP in the same season. Rosenbluth holds several UNC records, including most points in a single season, and highest single-season average. In the 1957 NBA Draft he was the sixth player chosen, picked by the Philadelphia Warriors. His professional career included a brief stint with the Warriors. He played for them from 1957–59. He played in 82 games, and averaged 4.2 points per game. After he retired from basketball, he had a long career as a high school teacher and coach. He ultimately moved with his wife to Chapel Hill, NC.