The Portugal star fired a shot just wide of the goal as he limbered up for the Champions League clash in Switzerland.
The ball cannoned into an unsuspecting steward standing behind the goal and the impact knocked her to the ground on Tuesday evening.
Cristiano Ronaldo accidentally KO’d a match steward while warming up on Tuesday evening
Ronaldo’s shot cannoned into an unsuspecting steward standing behind the goal
The steward was later given a United Ronaldo shirt as a peacemaking gift after the incident
Ronaldo jumped over the barrier to check on the welfare of the stricken steward as he received medical attention. The Portuguese star also apologised and later, she was pictured with her very own Ronaldo United shirt.
And Ronaldo quickly found his range to put the visitors ahead in the 13th minute.
Fernandes curled an inviting cross with the outside of his right foot and Ronaldo’s effort went in off the goalkeeper.
Ronaldo fired a shot just wide of the goal as he limbered up for Champions League tie
The Portugal star jumped over the barrier to check on the welfare of the stricken steward
The night ended on a sour note for Ronaldo, who became the joint all-time Champions League appearance holder by making his 177th appearance.
Manchester United were reduced to 10 men in the 35th minute after Aaron Wan-Bissaka’s dangerous challenge on Christopher Martins earned the defender a straight red card.
They still looked on set to take a point after Cameroon winger Moumi Ngamaleu’s equaliser in the 66th minute.
But a 95th-minute howler by substitute Jesse Lingard – who had replaced Ronaldo with 18 minutes left – allowed Jordan Siebatcheu to score the winner.