Ken Griffey Jr. became a huge star in Seattle, then beelined back home to play in Cincinnati.

Now that he's capped off his career with a trip to Cooperstown, a juicy question: Will Junior wear a Mariners or Reds hat on his Hall of Fame plaque?

Or maybe there's a third option, as reigning NL MVP Bryce Harper tweeted Wednesday.

That's how Griffey often flipped his lid, having fun while getting ready for games.

''I haven't really thought about the hat backwards,'' Griffey later said on a conference call.

As to his preference, he added: ''I'll think more about it tomorrow.''

The Hall of Fame actually makes the final call on caps. New inductees can express their wishes and talk it over with the Hall staff, but they don't get the last say. According to ESPN's Jim Bowden, the Hall of Fame left open the possibility of Griffey Jr.'s hat being on backwards on his plaque.

Griffey's best years came in Seattle. The slugging center fielder was an All-Star and Gold Glove winner for 10 straight seasons with the Mariners, and rejoined them to close his career.

Griffey played nine seasons with the Reds, often slowed by injuries. He hit 417 homers for Seattle and 210 for Cincinnati.

- With files from theScore