Seattle Seahawks part ways with Pete Carroll after nearly 15 years.
Team owner Jody Allen announces Carroll's role is evolving to adviser.
Carroll, emotional in a news conference, emphasizes the importance of fun.
Carroll joined the Seahawks in 2010, leading to the team's successful era.
Seahawks drafted quarterback Russell Wilson two years after Carroll's arrival.
Carroll and Wilson secured the team's first Super Bowl championship in 2014
Carroll made nine playoff trips in 14 years with a 137-89-1 record.