For now, however, with a glut of retired numbers coming down the pike, the Yankees have yet to figure out a solution to such a desirable problem.
"We haven't formalized anything," Cashman said at Pettitte's retirement news conference at Yankee Stadium. "I think it's important that a franchise try to create some boundaries. I'm a baseball operations guy. That's more of an ownership area.
"I think it would help from a fan's expectation to create criteria. Ownership makes those determinations. I would think that's something that should be done."
No one has worn Bernie Williams' 51, Joe Torre's 6 or Mike Mussina's 35 since they left. Paul O'Neill's 21 was given to reliever LaTroy Hawkins for the 2008 season, the first time anyone was assigned that number since he retired after 2001, before fan backlash convinced Hawkins to switch numbers in April.
Williams figures to be the first honoree, and Torre surely will get his number retired, too. Eventually, though, the Yankees will have to make these hard calls.
There's not a huge rush, though. Ron Guidry pitched his final game in 1988, and the Yankees didn't retire his number until 2003.