The winger missed a golden opportunity to equalise for the Hoops at Hampden Park.
Rangers were 1-0 up thanks to a Kenny Miller strike when the winger was presented with the perfect chance to level the scores.
After Leigh Griffiths' shot hit the post, Roberts was left with a practically open goal with Gers stopper Wes Foderingham on the other side of the goal having attempted to get to the previous effort. However, the 19-year-old was unable to put his effort on target much to the delight of the blue half of Hampden Park.
And with the game ultimately coming down to the lottery of a penalty shootout, it is fair to say that Roberts converting the chance may have helped Ronny Deila's men book their place in the final, which is a fact that has not been lost on the Manchester City loanee.
"It happens in football, you have to move on. I might be laughing about it but it was a very serious matter and I was really disappointed with myself," he told The Scottish Sun.
"No one can beat me up about it more than I've beaten myself up though.
"You'll get stick and banter but you have to get on with it.
"It's a learning curve for me. How big the game was, it was the worst possible time."
Though the disappointment of squandering a glorious opportunity on the big stage would have a hugely negative impact on most, Roberts has shown that he has the confidence in himself to make amends for the mistake.
He showed tremendous composure to score during the Hoops' victory over Hearts on Saturday - his third goal for the club, all of which have come against the same opposition - and clearly has the talent to ensure that he will be on the big stage on many more occasions during his career.