The 28-year-old was left on the bench for Chile's opening game of the Confederations Cup in Moscow after sustaining an ankle injury on Thursday, which forced the Arsenal star to subsequently miss training on Saturday.
Chile boss Juan Antonio Pizzi admitted that Sanchez was still feeling pain ahead of the match but went on to bring the forward on in the 58th minute as his team were being held to a goalless draw by Cameroon.
The move worked as Sanchez sent in the cross that Arturo Vidal headed into the back of the net in the 81st minute before he saw his added time shot blocked, which allowed Eduardo Vargas to drive in the rebound and secure a 2-0 victory at the Spartak Stadium
But after the Group B game, Sanchez took to his Instagram account to show the extent of his injury - with the Arsenal forward's left ankle appearing severely swollen as a result of his substitute appearance.
Pizzi, however, told reporters after the game that Sanchez did not suffer any further issues against Cameroon which could mean he gets some minutes when Confederations Cups debutants Chile play Germany on Thursday.
Pizzi said: "He [Sanchez] played a key role in both situations that led to a goal, so he's happy.
"I don't like mentioning individual players but we can be very happy that he plays in our national team. He always wants to play with us so we have to take care of him, even if that means he can't always be here when we want him."
He added: "All the players on the bench can join the game at any time.
"In this situation, when you have an excellent player of course you try to find a time when he can come on and we wanted to see that. He has had some health issues but he played well and didn't suffer any more problems.
"The match really required us to do something to score a goal and he's the right player for that. He's a very important player and that's why we put him on."