In his third year in the NBA, Gallatin was selected for the first NBA All-Star Game in 1951, and from 1951 to 1957 was chosen for seven consecutive NBA All-Star games. It was in the NBA where he earned the nickname "The Horse". He played his entire career as an undersized center at 6'6" and 215 lbs., but made up for it with tremendous physical strength. He played nine seasons for the New York Knicks, from 1948 to 1957. His best statistical year was in 1954, when he led the NBA in rebounding, averaging 15.3 rebounds per game. That same year, he was also named to the All-NBA First Team. His most dominating single-game performance was on the last regular season game of the 1952–53 season. That night, against the Fort Wayne Pistons, Gallatin pulled down 33 rebounds, a Knicks record which still stands today. In the six seasons he played when rebounds were recorded, he was among the leaders in the league in rebounds per game. For his career, he averaged 11.9 rebounds per game. Gallatin still holds the Knick team record of consecutive games played, with 610.