As a sixth successive draw between last season's Europa League finalists was seemingly on the cards, the Portuguese legend was able to poke the ball home from a tight angle in the 95th minute to secure a 2-1 victory for the Red Devils, sparking wild scenes in the Stretford End.
That crucial strike from the 36-year-old means he has found the back of the net three times in second-half stoppage time, moving him level with Aguero, who himself scored a dramatic winner against the Yellow Submarine 10 years ago at the Etihad Stadium.
Ronaldo also broke the all-time Champions League appearance record by featuring for the 178th time on Wednesday, surpassing former Real Madrid teammate Iker Casillas who had held the record since September 2015.
Since returning to Old Trafford this summer, Ronaldo has scored five goals in as many appearances across all competitions, with his most recent strike taking his overall tally as the Champions League's all-time record goalscorer to 136, 15 clear of his nearest challenger Lionel Messi.
Victory for Man United against Villareal means they now sit third in Group F, level on points with Young Boys – who beat the Red Devils in the opening gameweek – and one point behind group leaders Atalanta, who Ole Gunnar Solskjaer's side face next in three weeks' time. body check tags ::