Fernando Santos left the Real Madrid star on the bench against Andorra because a yellow card would see him miss the fixture against Switzerland. However, Portugal were unable to score and the coach decided to take a risk in the second half.
The reigning European champions returned to the dressing room at the break with the scoreline unaltered. Fernando Santos decided to bring on Cristiano Ronaldo.
Portugal's head coach was forced to make an emergency decision with their place in next year's World Cup at stake and the Real Madrid star came on for the second forty-five minutes.
Ahead of the fixture, the Portuguese were focused mostly on the crucial game against Switzerland on Tuesday, but a win over Andorra is vital to maintain their hopes of topping Group B.
Ronaldo, who trained alone this week, did not hesitate when taking the captain's armband and jumping on to save his team.