Caserio joined the Patriots in 2001 as a personnel assistant. In 2002, he served as an offensive coaching assistant coach for the team, while in 2003 he moved to the scouting department as an area scout. Caserio served as the Patriots' director of player personnel from 2004 to 2006 prior to spending the 2007 season as wide receivers coach.
In 2008 he returned to the personnel department, as director of player personnel. He remained in that position even after Vice President of Player Personnel Scott Pioli departed in 2009 to become general manager of the Kansas City Chiefs; former Tennessee Titans general manager Floyd Reese was brought in as a "senior football advisor."[1] Throughout the 2009 preseason, however, Caserio assisted the offensive coaching staff, which included new wide receivers coach Chad O'Shea and tight ends coach Shane Waldron. Caserio also continued to assist the coaching staff from the press box during games along with football research director Ernie Adams