After becoming outstanding in the grid sport, Brewster made his way into the NFL. In his first season with the Cleveland Browns, he filled in on both defense and offense. He became the team's first-string offensive left end during his second season and was the team's second-ranking pass receiver during the 1953 season. He was selected for Pro Bowl honors in 1955 and 1956 at the tight end position. After seven seasons with the Browns, he played for the Pittsburgh Steelers for two seasons.