Estes was recruited out of Washington High in Los Angeles to play football for the University of Colorado, which at the time was in the
Big 8 conference. Estes made his debut in 1964, playing on a Buffaloes team that was ranked 110th in the national out of 120. The team went through a bevy of quarterbacks, Bernie McCall, Hale Irwin, and Dan Kelly, and none could lead the team to success. The Buffaloes finished with a record of 2-8 under head coach
Eddie Crowder. For his first season in college football, Estes ended up with 81 carries for 273 yards and one touchdown. The following season, the Buffaloes improved. They finished with a 6-2 record, quarterback Bernie McCall led the conference in completion percentage, and Estes was the number one back, carrying the ball 114 times for 317 yards and five touchdowns. However, Estes saw his playing time and carries reduced in favor of Wilmer Cooks. Estes finished his college career with 230 carries for 726 yards and seven touchdowns. ==Pro Career==