The actor took home the award for his performance in the biopic King Richard, in which he played Richard Williams, father of tennis champions Serena and Venus Williams.
In a shocking incident that dominated discussion around the event, Smith walked on stage and appeared to strike Rock after the comedian made a joke about his wife, the actor Jada Pinkett Smith.
Smith was then heard yelling: “Keep my wife’s name out your f***ing mouth.”
In an emotional speech after his Oscar win, Smith said: “Richard Williams was a fierce defender of his family.”
He continued: “I’m being called on in my life to love people and to protect people and to be a river to my people. I know, to do what we do, we’ve gotta be able to take abuse. You’ve gotta be able to have people talk crazy about you. In this business, you’ve gotta be able to have people disrespecting you.
Dyring his speech, the actor also revealed what Washington said to him directly after he hit Rock.
Up against Smith in the category were Javier Bardem in Being the Ricardos, Benedict Cumberbatch for The Power of the Dog, Andrew Garfield inTick, Tick… Boom! and Denzel Washington in The Tragedy of Macbeth.
Click here for a list of the winners.
The I Am Legend star had been the heavy favourite to take home the prize.
The win represents Smith’s first victory at the Academy Awards, having been nominated twice previously for Ali and The Pursuit of Happiness.
In her four-star review of King Richard for The Independent, Clarisse Loughrey wrote: “For all [the] transformation (there’s even a Louisiana accent in play), what actually makes Smith such a ferocious asset to King Richard is the one thing that couldn’t be scrubbed out.”
She continued: “He is a true movie star in an age where there are diminishingly few – and with that comes a certain sense of command, a largeness to his presence that reaches beyond the confines of the film itself.”
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