Education
Grennan graduated from Edmonds-Woodway High School in 2002.
Grennan graduated from Edmonds-Woodway High School in 2002.
He most recently played for the Hartford Colonials of the United Football League. He was signed by the San Diego Chargers as an undrafted free agent in 2007. He played college football at Eastern Washington.
He was a first team All-WesCo 4A South League selection and was a Seattle Times All-Area performer.
He helped block for running back Kyle Thew, who had a pair of 300-yard rushing games. In 2005 he started four games at defensive tackle, including Eastern"s last three games of the year.
In 2004 he lost a year of eligibility after having to sit out the 2004 season because of National Collegiate Athletic Association transfer rules. CWU: Played as a tight end in the 2003 season at Central Washington University after redshirting in 2002.
He finished the 2003 season with 12 catches for 157 yards (131 per catch) with no touchdowns.
San Diego Chargers
Grennan signed two-year contract with the San Diego Chargers as an undrafted free agent on May 4, 2007. Cleveland Browns
Grennan was signed to the Cleveland Browns" practice squad prior to the 2009 offseason. He was waived on October 9, 2009 and re-signed to the practice squad on October 20.
After his contract expired following the 2009 season, Grennan was re-signed to a future contract on January 5, 2010.
UFL
Grennan signed with the United Football League Hartford Colonials for the 2011 season. He became a free agent on August 10, 2011, when the Colonials were contracted by the UFL.
He has also been a member of the Cleveland Browns.
