He played college football for the Minnesota Golden Gophers and was selected by the New England Patriots with the 21st overall pick in the 2006 NFL draft.
Maroney attended Normandy Senior High School in St. Louis, Missouri, where he gained four varsity letters in football, three in track, two in basketball, and one in baseball.
Maroney declared for the 2006 NFL draft after the completion of his junior season and was selected in the first round with the 21st overall pick by the New England Patriots.
However, two weeks later, Maroney suffered torn rib cartilage against the Detroit Lions on December 3 and missed the Patriots' next two games.
In the playoffs, Maroney became a bigger factor for the Patriots, compiling 244 rushing yards and two touchdowns in two games before playing in Super Bowl XLII.
[10] After he was inactive for the Patriots' 2010 season opener against the Cincinnati Bengals, Maroney was traded to the Denver Broncos on September 14, 2010.