Mourinho confirmed Sanchez who has not scored a goal in four games this season, would return on Saturday.
Marouane Fellaini gets a recall in midfield as he replaces the suspended Nemanja Matic alongside Fred and Paul Pogba while Jesse Lingard comes back in to the attack having been rested for the Champions League win over Young Boys. I think the team is more compact, is more solid, the spirit, the co-operation, the empathy, the communication, all of that improved in the team and good results bring confidence.
"I want him, in this process of adaptation, to play totally fresh, so he's not playing tomorrow", Mourinho said.
Mourinho believes his team will be better this campaign than they were last, when they finished a distant second to Manchester City.
Mourinho refused to single out the 29-year-old but, in answer to a question specifically about Sanchez, challenged his entire squad to get better.
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Liverpool boss Jurgen Klopp says that midfielder James Milner is setting "the best example" to the rest of his first-team squad. I am fine with him, I think he is fine with me and the situation, so that's all.
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They lost the sixth game that season 1-0 at Manchester City and this weekend's trip to West Ham is far from a certainty. So I don't know who will be the striker of the future but I think both because we have to play 60 matches.
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While last season all the praise was lavished on Liverpool's front three, so far it has been the midfield which has been winning all the plaudits.
"He suited the team and I'm very happy to see him play like that".
Because Martial play 90 minutes [against Young Boys] and Sanchez played zero'.
"I think the team is resolving the defensive problems better than before", Mourinho said.
"A team that yesterday looked very bad, today looks very good and yesterday looked very good, today looks very bad". 'Every player has another level to step up'.
"I think we are improving as a team".
"It's more about the moment and the momentum is very important in the positive and negative way".