The man who stood to gain most from the dismissal betrayed nothing through his expression and gentle clapping - a survival tactic honed during five decades of service to the mercurial Mugabe. His cap, however, spoke volumes.
Emblazoned across its front, next to a portrait of Mugabe, were four words: “Indigenise, Empower, Develop, Employ” - a slogan of the ruling ZANU-PF party.
Speaking at the congress, Mnangagwa reinforced the message from his headgear, announcing revisions to the party’s constitution that backed “total ownership and control” of Zimbabwe’s natural resources.
It was a key insight to the party’s direction as it contemplated life beyond Mugabe.
“We will remain forever masters of our own destiny,” Mnangagwa said, to cheers from the crowd.
With Mugabe, 93, held following Wednesday’s military takeover in Harare, questions have arisen about what the future holds for Mnangagwa, whose sacking from the post of vice president last week brought the political crisis to a head.
“There are no arguments around his credentials to provide strong leadership and stability, but there are questions over whether he can also be a democrat,” said Eldred Masunungure, a political science lecturer at the University of Zimbabwe.
The whereabouts of Mugabe’s wife Grace, 52, whose prospects of succeeding the president appeared to have been helped by Mnangagwa’s dismissal, are presently unknown.
With his appointment in 2014 as official deputy to Mugabe, Mnangagwa had appeared well set as the eventual successor to Africa’s oldest head of state.
The 75-year-old was one of Mugabe’s most trusted lieutenants, having been at his side in prison, during wartime and then in government.