Despite playing his club football in Saudi Arabia with Al-Nassr, Ronaldo was present in Monaco for the draw of the inaugural league phase of the competition.
The Portuguese star was presented with a special award to honour his all-time Champions League scoring record of 140 goals.
However, given the new format of the competition, Ronaldo didn't have much to do during the draw itself, with automated software being used.
One fan joked: 'Ronaldo is so bored of that button'.
Fans joked that Cristiano Ronaldo looked 'so bored' as the Champions League draw took place
Meanwhile, another user commented that Ronaldo was 'allocated the role of an IT worker'. They wrote: 'UEFA essentially bringing Cristiano Ronaldo, one of the modern footballing greats, in for the Champions League draw just to push a button to run a computer script... basically allocated the role of an IT worker.'
In addition, another user stated that UEFA's use of Ronaldo epitomised the organisation's 'silliness'.
They wrote: 'Paying Ronaldo to fly in to stand on a stage to simply press a giant button - literally all he is doing - might be the single best ever capture of UEFA silliness'.
One user commented that Ronaldo 'looks so bored'. They wrote: 'Flying all the way from Saudi to Monaco to press a button. Looks so bored Ronaldo.'
Furthermore, another user jokingly wrote: 'Cristiano, you pressed the button for your former club, Real Madrid, thoughts?'.
Another user commented that Ronaldo looked 'p***** off'. They wrote: 'Cristiano Ronaldo has turned up just to push a button and he seems absolutely p***** off about it.'