"We don't know what we're doing next year with respect to Seattle. It's all rumors," Griffey told the Associated Press, adding, "I really don't even know. My agent is handling."
Both the agent, Brian Goldberg, and Mariners general manager Jack Zduriencik maintained radio silence.
Zduriencik would neither confirm or deny that a deal is imminent, saying, "I do not comment on free agents."
The deal would not be finalized until Griffey passes a physical, which is expected to occur in the Phoenix area.
Griffey had arthroscopic surgery on his left knee in October to repair a partially torn meniscus and cartilage and the tending physician said the 39-year-old outfielder has completely recovered.
The injury, suffered last April when he accidently bumped into a trunk inside the Reds clubhouse, has been blamed for the lack of power he displayed with the Reds and later in the season with the White Sox.
After hitting 30 home runs and driving in 93 runs for the Reds in 2007, Griffey hit 18 home runs and drove in 71 runs last season. The fact he couldn't push off his back (left) leg deprived him of power.
The Mariners are hoping to get the '07 version.
Besides giving the team a much-needed run producer, Griffey's return could significantly increase ticket sales, which have been slow because of the struggling economy and the fact that the organization is coming off its first 100-loss season in 25 years.
Griffey comes into the season -- his 19th in the Major Leagues -- as the active career home run leader with 611. The first 398 home runs of his career were hit with the Mariners, from 1989, when he was known as The Kid, through 1999.
A 10-time All-Star during his 11 seasons with the Mariners, Griffey reached superstar status in the early 1990s, when he helped put Seattle on the big-league map, and the mid-90s, when he hit 49, 56, 56, 48 and 40 home runs during a five-year stretch.
In 1997, he became the first Mariners player to be selected as the American League's Most Valuable Player.
Junior hastened his departure from Seattle in 1999, requesting a trade so he could be closer to his wife and two children in Orlando, Fla. Pat Gillick, then the general manager, granted that wish, dealing Griffey to the Reds for center fielder Mike Cameron, pitcher Brent Tomko, infielder Antonio Perez and Minor Leaguer Jake Meyer.
Griffey returned to the city where he virtually grew up. His dad, Ken Griffey Sr., was a big part of the Big Red Machine during the 1970s.
But numerous injuries cost Griffey playing time during his nine years with Cincinnati.
Gone from Seattle but never forgotten, Griffey returned to the city in June 2007 for a three-game Interleague series.
It was a virtual lovefest as fans filled Safeco Field for all three games and presented Junior with numerous standing ovations.
Before the series-opening game, the Mariners honored him with a 15-minute presentation that included a highlight reel of his playing career with the Mariners and a presentation of a "The House that Griffey Built" memorial by club president Chuck Armstrong, which drew a four-minute standing ovation.
Griffey hit two home runs in the final game of the series and in a TV interview broadcast on the local FSN affiliate following the series finale, Griffey emotionally expressed an interest in returning to the Seattle ballclub in the future should circumstances warrant it.
Griffey said during the interview that he would like to end his career as a Mariner and felt that he owes it to the fans of Seattle.
"I think for the simple reason that this is the place where I grew up and I owe it to the people of Seattle and to myself to retire as a Mariner," he said.