The Red Devils brought in the Chile international from Arsenal as they opted to allow Henrikh Mkhitaryan to leave Old Trafford and move to The Emirates as part of the same deal.
Sanchez’s arrival at Old Trafford has increased the competition for places at the club and has seemingly made it more difficult for Rashford to earn a place in the starting line-up.
And former Liverpool FC midfielder Redknapp admits that he feels sorry for the England striker, although he has told him that he must simply step his game up and keep competing for a place.
Writing in his column for Sky Sports, Redknapp said: “Mourinho has said Sanchez can be an inspiration to Rashford but I don’t think that’s what he needs right now. We’re talking about an established England international.
“There is only one way to learn, and it’s not by sitting next to someone in the dressing room, it’s by playing in the team.
“I feel sorry for him, but all he can do now is go into training every single day and show that he can become a better player than Sanchez. That’s really his only option.”
Both Rashford and Sanchez will be hoping to feature for Manchester United when the Red Devils when they take on Newcastle United at St James’ Park on Sunday afternoon.
Manchester United are currently in second place in the Premier League table as they chase a top-four finish in Jose Mourinho’s second season in charge at Old Trafford.
The Red Devils will take on Sevilla in the last 16 of the Champions League later this month.
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