In 1979, he helped lead the Rams to Super Bowl XIV, where they were defeated 31-19 by the Pittsburgh Steelers. In 1984, he rushed for a 49er team record 1,262 yards during the regular season, and also caught 28 passes for 230 yards, was selected to the Pro Bowl, and played in Super Bowl XIX in which the 49ers defeated the Miami Dolphins 38-16. Tyler was the first player ever to lead two different teams in rushing in two different Super Bowls.
Tyler played running back at UCLA from 1973–1976 and is fifth in career rushing yards for the Bruins, with 3,240 yards. 1976 All-Conference and 3rd team All American, Tyler was on the 1975 UCLA team that won the Pacific-8 Conference and defeated number one ranked Ohio State in the Rose Bowl.