11:53am: The Mariners confirmed the news in a press release. A quote from Griffey:
I look forward to contributing in any role that Don (Wakamatsu) sees fit on the field, and any manner I possibly can off the field.
10:54am: The Mariners have reached an agreement on a one-year deal with Ken Griffey Jr., according to Larry Stone of the Seattle Times. ESPN's Jerry Crasnick says Junior's new contract is similar to last year's. SI's Jon Heyman says it's a $2MM base with incentives that could exceed $1MM. The Griffey signing did no harm a year ago, but this time around it makes less sense.
Griffey, who turns 40 soon, hit .214/.324/.411 in 454 plate appearances, earning $2MM plus incentives. He mostly served as the team's DH, logging 83 outfield innings. Griffey had arthroscopic knee surgery last month.