Robertson attended Melrose High School in Memphis, Tennessee and was a letterman in football. In football, he was a two-time All-Metropolitan Memphis honoree and a two-time All-State honoree.
College career
Robertson attended college at the University of Kentucky. He originally intended to play H-Back, but was later converted back to defensive tackle after several key drops in spring practice. As a freshman, he was named Freshman All-SEC by the league's coaches. In his junior season in 2002, Robertson recorded 48 tackles, five sacks for -40 yards, 13 quarterback pressures, a pass defensed, and a blocked kick, earning a second-team All-SEC selection. Robertson decided to forgo his senior season and enter the 2003 NFL Draft. He finished his collegiate career with 114 tackles, one fumble recovery, three forced fumblesand 10.5 sacks in three seasons.
Professional career
2003 NFL Draft
Robertson was chosen by the New York Jets after his junior year with the 4th pick of the 2003 NFL Draft. He was the highest selected defensive player from Kentucky since Art Still went second overall in the 1978 NFL Draft.
New York Jets
He started all 16 games during his rookie season, recording 43 tackles and 1.5 sacks. He was the first Jets defensive player to start every game in his rookie season since Mo Lewis in 1991. He played in all 16 games in 2004, totaling 52 tackles and 3 sacks. He had 7 tackles in the Jets’ 20-17 overtime Wild Card playoff victory on the road against the San Diego Chargers. Robertson played in 13 games, tallying 43 tackles, 3.5 sacks, and 1 pass breakup. For the first time in his career, he missed a game in Week 15, due to an injured thigh. On November 14, 2006 Robertson was named the AFC Defensive Player of the Week for Week 10. He had six tackles and a sack in the Jets' Week 10 win over the New England Patriots. Robertson's career with the Jets was labeled as a bust, considering the high expectations and the Jets efforts to trade up to draft him. On March 3, 2008, ESPN.com reported that Robertson has been traded to the Bengals. However, later that same day, FOXSports.com broke the news that Robertson and the Bengals were unable to come to terms on a new contract, resulting in the trade falling through.
Denver Broncos
On April 24, 2008, the Jets reached an agreement to trade Robertson to the Denver Broncos for a late-round conditional pick in the 2009 NFL Draft. This pick could have escalated as high as a second rounder based on the statistics and performance of Robertson. Upon acquiring Robertson, the Broncos signed him to a five-year contract believed to be worth about $24 million. Robertson was released by the Broncos on February 16, 2009 after just one season with the team.
