"Mr. Yoshioka has a lot of opportunity to make a lot of money in his group, so the race is not over," said Stringer. "There are no guarantees about who gets promoted next," he added.
Stringer declined to give a timetable on deciding a successor. He also said his three positions of chairman, CEO and president could be split up and not all go to the same person.
External candidates were considered but Sony is no longer looking at outsiders.
"I think it would be destructive to bring in an outside player," Stringer said, explaining how hard it would be for an outsider to grasp the complexity of the company. "I think it would be destructive to morale, it would be destructive to performance," he said.
A decision could be years away. Stringer has extended his commitment to remain at Sony, though he did not offer a specific time frame.
"The board asked me to stay on and I'm happy to do so because there is unfinished business," said Stringer.
Stringer became chairman and CEO of Sony in 2005, a time when its core electronics business was struggling. He has said in the past he would leave the company when its turnaround was complete. With that in mind, any clues as to the identity of his successor have been keenly watched.
Sony will reorganize its core electronics operations into two main divisions from April 1, with Hirai and Yoshioka leading the units. The move positions the two executives to potentially succeed Stringer one day as chairman of the electronics giant. Originally, there were four men in the running for Stringer's job, all Japanese.
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