The Chile international moved to the Red Devils in a swap deal from Arsenal despite being linked with a potential switch to Premier League champions Manchester City over the past 18 months or so.
Sanchez, though, sealed a swap move to Manchester United as Armenia international Henrikh Mkhitaryan secured a switch in the other direction after falling out of favour under Jose Mourinho.
Sanchez scored two goals in his opening 14 games to make an underwhelming start to life at Old Trafford and Mourinho even dropped the South American from his match day squad for last week’s 2-0 win at Bournemouth.
However, the South American impressed in Manchester United’s 2-1 win against Tottenham in the FA Cup semi-final after the Chilean cancelled out Christian Eriksen’s opener before Ander Herrera’s winner.
Former Liverpool FC captain Redknapp insisted that he anticipated Sanchez would find life tough at Manchester United given the Chile star is no longer the main man at Old Trafford.
“I am not surprised that Sanchez has taken time to get going,” Redknapp told the Daily Mail.
“He has gone from being the best player at Arsenal to just another member of Jose Mourinho’s squad.
“With Anthony Martial, Marcus Rashford and Jesse Lingard all vying for places in United’s front line, Sanchez has not known where he fits in the jigsaw.
“He is a player who needs to be the main man. This goal — his eighth in as many games at Wembley — will give him renewed confidence.”
Manchester United are in second place in the Premier League table and three points ahead of Liverpool FC.
The Red Devils lost 2-1 to La Liga giants Sevilla in the Champions League round of 16.
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