The Manchester United goalkeeper pulled off eight saves throughout the game to thwart danger from the hosts.
The most crucial ones are shown below, have a look - each at key moments in the game.
He made a great block to deny a Villa chance right after Man United opened the scoring.
He immediately saved another one just one minute later.
After the break, Onana once again sprung into action to deny Villa, who were also not clinical enough with their finishing.
Onana should have kept a clean sheet in this one for his consistency at making saves - something he's been criticised for.
He was unlucky to concede Douglas Luiz's goal as he saved the first attempt but was unable to keep out Villa's second attempt seconds later.