Nissan just named a new chief executive in the wake of Carlos Ghosn's arrest and dismissal. Now, it seems, it could get another.

According to Bloomberg, Hioto Saikawa – the erstwhile Ghosn protege who blew the whistle on his former boss – is preparing to "pass the baton" on to another in the coming months as his #1 task of reforming Nissan's governance that was (allegedly) so deeply compromised by its incarcerated former chairman and CEO. But just who will take over from him, and where the next chief exec will take the company, remain big question marks.

Saikawa-san first joined Nissan in 1977 immediately after graduating from Tokyo University, and has been with the company ever since. Along the way, he's served as head of purchasing, research and development, manufacturing, and the American- and European-market management committees (to name just a few of the portfolios he's held over the years). He also serves as chairman of the influential Japan Automobile Manufacturers Association, and for ten years sat on the board of corporate ally Renault.

That alliance stands to change under the new management instituted at both Nissan and Renault in the wake of Ghosn's departure.

The embattled French/Lebanese/Brazilian executive is widely seen as the glue that bound Renault and Nissan (and now Mitsubishi) together under an often shaky alliance. And his replacements could yet see the value in their predecessor's vision. But even if they were to put some space between them, divorcing the members of the alliance wouldn't be as simple as passing a motion at a board or shareholders' meeting.

Renault owns 43 percent of (and significant voting rights at) Nissan, which in turn holds 15 percent (but less voting rights) in Renault (along with 34 percent of Mitsubishi).