Romelu Lukaku gave the home side the lead in the fifth minute at Old Trafford before Sanchez made it 2-0 to the hosts in the 20th minute to notch up his second goal for the club.
Sanchez has been under the spotlight since his move to Manchester United from Arsenal in the January transfer window, with the 29-year-old having struggled to find his best form for the Red Devils.
And Mourinho believes that his goal against Swansea will help him to rediscover his confidence as Manchester United look to try and end the season on a high.
Speaking at his post-match news conference at Old Trafford on Saturday afternoon, Mourinho said:“Alexis to score a goal is nice for him, for his confidence, but again it was our best period in the game and 2-0 was really short to arrive at half-time.”
Manchester United will now switch their attentions towards their trip to Manchester City in the Premier League next weekend.
The Red Devils know that Manchester City can win the Premier League title if they beat Mourinho’s men at The Etihad.
Manchester United are currently in second place in the Premier League table as they look to try and win the FA Cup and finish in the top four this season.
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