The Chilean winger has stated that Barcelona will have to fight to rescue their last-16 Champions League tie and is under no illusions at the size of the challenge on Tuesday
The Blaugrana go into the fixture after a 2-0 Liga win over Deportivo La Coruna, a game in which Sanchez opened the scoring before Lionel Messi added a late second, but the Chile international acknowledges that Tuesday's tie will be a very different proposition.
"We had to win, it was important," the former Udinese forward told journalists after the game.
"We also have to win on Tuesday against Milan. Defeats in these matches leave a mark, but on Tuesday there is a battle we must win one way or another."
Barcelona face a daunting task as they attempt to overcome the Rossoneri and continue their pursuit of a fifth European crown, but midfielder Thiago Alcantara insists the squad is full of belief.
"We’re playing for our lives in the Champions League, the most important title there is," the 21-year-old was quoted as saying by Mundo Deportivo.
"We’ll try to get a good result. Victory helps us boost our morale. We’re optimistic ahead of the match against Milan."