The Chile international had been finding himself in the firing line this season after failing to produce consistent performances for the Red Devils under Jose Mourinho.
Indeed, Sanchez was dropped from the matchday squad completely for the 3-1 loss to West Ham United at the London Stadium earlier this week to raise doubts about his future at the club.
The 29-year-old has generally struggled to produce consistent displays for the Red Devils since his move to Old Trafford from Arsenal in the January transfer window.
However, the attacker earned hero status on Saturday evening when he came off the bench in the second half to fire home the winner for Manchester United against the Magpies.
The victory was a crucial one, and came only after Juan Mata and Anthony Martial had brought the Red Devils level after they found themselves 2-0 down to Rafael Benitez’s men at half-time.
And Lukaku has insisted that Sanchez deserved to be the hero on Saturday because of the work he has been putting in behind the scenes at Carrington.
“I would have wanted to have been in his shoes today [scoring the winner], but the guy is working really hard,” said Lukaku, speaking in an interview with MUTV after the game.
“I think he’s one of the most hard-working professionals I have ever seen and to give us the win, he deserves it and I am really happy for him.”
Sanchez has scored one goal and made one assist in six Premier League appearances this season, but he has only started four of the Red Devils’ eight top flight outings.
Manager Mourinho added: “I think he is a good boy.
“A good professional who works really hard. He is not playing especially well, in some periods, but, when the team doesn’t play especially well, it’s difficult for players individually to perform well.
“Today, I think it’s an amazing feeling for him to score the winning goal in a comeback. That is nice.”
Meanwhile, Manchester United will now turn their attentions towards the small matter of the crunch showdown against Chelsea FC at Stamford Bridge after the international break.
The Red Devils will travel to west London on 20 October as they look to make it back to back wins in the Premier League and try and get themselves back on track after a stuttering start to Mourinho’s third season in charge.
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