“In my 10 years with the Lions and the Rams, I never missed a game,” Brown said in a 2015 interview with the Virginian Pilot. “I had broken hands and broken bones. But probably not as many as I caused. I had 12 operations.”
After playing on the defensive line on the Penn State University football team, Grier was drafted as the 31st overall pick in the third round of the 1955 NFL Draft by the New York Giants. He played with the Giants from 1955 to 1962, during which he led the team to an NFL Championship in 1956 and the Eastern Conference Championship in 1958, 1959, 1961 and 1962. Grier was selected for the Pro Bowl in 1956 and 1960, and was named All-Pro at the defensive tackle position in 1956 and 1958–1962.
Grier was then traded in July 1963 to the Los Angeles Rams in exchange for defensive tackle John LoVetere and a high future draft pick. He was part of the "Fearsome Foursome", along with Deacon Jones, Merlin Olsen, and Lamar Lundy,[9] considered one of the best defensive lines in football history. His career ended in 1967 due to a torn Achilles tendon. Despite being the oldest member of the Fearsome Foursome, Grier is the last surviving member following the death of Deacon Jones on June 3, 2013