The appointments may begin to ease a Renault-Nissan leadership crisis that erupted after Ghosn's Nov. 19 arrest in Japan and swift dismissal as Nissan chairman.
Senard, 65, now faces the task of soothing relations with Renault's Japanese partner and resuming talks on a new alliance structure to cement the 20-year-old partnership.
"It's important that this alliance remain extremely strong," Senard told reporters after a board meeting - citing the mounting investment demands of new vehicle technologies.
"It is our compulsory duty to go forward together."
Ghosn's exit also marks a clear end to one of the auto industry's most feted careers, two decades after he was despatched by former Renault boss Louis Schweitzer to rescue newly acquired Nissan from near-bankruptcy - a feat he pulled off in two years.
After 14 years as Renault CEO and a decade as chairman, Ghosn formally resigned from both roles on the eve of the board meeting.
Ghosn's arrest and indictment for financial misconduct has strained the Renault-Nissan relationship, threatening the future of the industrial partnership he transformed into a global carmaking giant over two decades.
For two months, the tensions deepened as Renault and the French government stuck by Ghosn despite the revelation he had arranged to be paid tens of millions of dollars in additional income, unbeknownst to shareholders.
Ghosn has been charged with failing to disclose more than $80 million in additional compensation for 2010-18 that he had agreed to be paid later. Nissan director Greg Kelly and the Japanese company itself have also been indicted.
Both men deny the deferred pay was illegal or required disclosure, while not contesting the agreements' existence. Ghosn has denied a separate breach of trust charge over personal investment losses he temporarily transferred to Nissan in 2008.
Ghosn had agreed in recent days to step down from Renault, Reuters reported on Tuesday - but only after the French government, Renault's biggest shareholder, called for leadership change and his bail requests were rejected.
Senard, who had been due to retire from Michelin in April, now has fences to mend in Japan.