Landsberger attended Mounds View High School (Arden Hills, Minnesota) where he graduated in 1973 after leading the Mustangs to the 1972 Associate of Arts State Championship as a junior. Landsberger then attended Allan Hancock College, where he was the California junior college player of the year, the University of Minnesota, and Arizona State University.
At 6"8" and 225 pounds, he played as a power forward and center. In his senior campaign, he averaged 26.1 points per game, and led the Mustangs back to the state tournament and the consolation championship. Over his high school varsity career, he scored 1,290 points and grabbed 910 rebounds.
At Arizona State University, he set school records for most rebounds in a game (27) and highest rebounds-per game average in a season (144).
After college, he was selected by the Chicago Bulls in the second round of the 1977 National Basketball Association Draft. He appeared in 196 games for the Bulls from 1977 to 1980, averaging 7.4 points per game and 7.6 rebounds per game.
On January 28, 1979, Landsberger grabbed 29 rebounds in a game against the Denver Nuggets. At the time, this was the third-highest single-game rebounding total in Chicago Bulls history.
That season, Landsberger ranked seventh in the league in total offensive rebounds, with 292.
On February 13, 1980, the Bulls traded Landsberger to the Los Angeles Lakers in exchange for Oliver Mack and two second round draft choices. Landsberger remained in Los Angeles until 1983. Playing behind future hall-of-famers like Kareem Abdul-Jabbar, James Worthy, and Magic Johnson, he never averaged more than 5.7 points or 5.5 rebounds in a single season with the Lakers.
Landsberger spent the 1983-1984 National Basketball Association season with the Atlanta Hawks.
He averaged 1.5 points and 3.5 rebounds in 35 games. This was his last season in the National Basketball Association, and he ended his National Basketball Association career with 2,468 total points and 2,681 total rebounds.
He played professionally in Europe until the 1990s. Among the highlights of his European career was a 34 rebound game while playing for Lotus Montecatini Terme in Lucca/Italy on November 11, 1990.
That performance set a record for most rebounds in an Italian league game.
Landsberger also set Greek league records for most rebounds in a game (37) and highest rebounds-per-game average for a season (179).
