In an interview with NFL Media's Steve Wyche at the NFL Annual Meeting, Harbaugh compared Martin with another Niner who became a solid role player once he moved to the Bay Area.
"Someone like Glenn Dorsey," Harbaugh said of his expectations for Martin. "Glenn was the No. 2 pick (Note: No. 5) in the draft. Maybe not living up to someone's expectations there, comes to the San Francisco 49ers and has a tremendous year. ... It's just a powerful opportunity, a powerful motivator."
Of course, Dorsey isn't coming off creating national headlines that led to an investigation of his previous locker-room culture, like Martin. In regards to that, however, Harbaugh once again went to his favorite clean-slate metaphor.
"Like an Etch-A-Sketch," the coach said of Martin's future. "Lifting a page of the Etch-A-Sketch and write a whole new history for yourself."
The 49ers coach said he didn't plan to ask Martin about his experiences in Miami.
"No. I didn't ask him anything," Harbaugh said. "I told him I didn't want to know anything, unless he wants to share it with me. ... If you want to take that (expletive) and flush it -- I'm all for it."
Harbaugh said Martin will have to earn respect and playing time in San Francisco.
"It's a 50-50 thing," Harbaugh said. "The burden is not completely on the locker room. You can't put that kind of burden on that locker room. The locker room embraces the guy that is about the team, and is serious about winning."