Shaun Alexander doesn't seem too worried about his former squad after the Seahawks missed the playoffs for the first time in 6 seasons ... telling TMZ Sports, "It just happens with age. Life happens."
Alexander would know ... he crushed it for the Hawks from 2000 to 2007, leading the team to Super Bowl XL to cap off the 2005 season.
"We went on a nice run when I was there," Alexander said ... "About 5 years in a row. They've kinda done it again."
Shaun's point ... teams move in peaks and valleys (except the Patriots) -- and it sounds like he's confident Seattle will find its way again.