Complex sentence: Garth DeFelice was a National Football League (NFL) umpire since the 1998 NFL season, wearing uniform number 53, who served in crews headed by Clete Blakeman from 2010-2013.
Split into simpler sentences: Garth DeFelice was a National Football League (NFL) umpire from the 1998 NFL season until 2013. His uniform number was 53, and served in crews headed by Clete Blakeman from 2010-2013.