Marrio Darnell Grier (December 5, 1971 – March 15, 2022) was an American professional football running back in the National Football League who played two seasons for the New England Patriots. He played college football for the Clemson University before transferring to University of Tennessee at Chattanooga. He also played as a running back and linebacker in the Arena Football League for the Carolina Cobras and Colorado Crush. Grier died on March 15, 2022, at the age of 50.