The Red Devils forward was disappointing in a goalless draw with La Liga side Valencia in their second Champions League group stage fixture at Old Trafford on Tuesday night.
Sanchez, who was left out of the Manchester United team for their 3-1 loss at West Ham United last weekend, looked off the pace on the right side of Manchester United’s attack.
Unsurprisingly, Jose Mourinho hauled off the South American forward in the 76th minute to the delight of some Manchester United supporters at the Theatre of Dreams.
Sanchez has failed to get on the score sheet in six appearances in all competitions in the current campaign to heap pressure on the former Udinese forward.
Given his poor performance in the Champions League, Sanchez could be facing a battle to retain his place in Mourinho’s team for the visit of Newcastle United in the Premier League on Saturday.
Former Arsenal forward Nicholas believes Sanchez should cut his losses and look to leave Manchester United in the January transfer window.
“I always said this when he was at Arsenal,” Nicholas told Sky Sports.
“He sat on that left-hand side, and sulked and sulked and sulked. He was a street-fighter, a warrior. That’s gone, those days have gone. Sanchez is no more.
“He’s got to get out of Manchester United because these fans aren’t interested in watching him.”
Sanchez moved to Manchester United in January despite defending Premier League champions Manchester City showing an interest in the 29-year-old attacker.
The South American forward has scored three goals in 25 games in all competitions since his move to Old Trafford in a swap deal as Henrikh Mkhitaryan moved to Arsenal.
Mourinho is facing speculation about his future as Manchester United manager and the Portuguese head coach will be eager to rely on players who can guarantee a performance.
The Red Devils will welcome winless Newcastle United in their next Premier League fixture in what should be a straightforward assignment for the 20-time English champions at Old Trafford.
Manchester United are in tenth place in the Premier League table and nine points behind leaders Manchester City and five points adrift of fourth-placed Tottenham Hotspur.
The Red Devils have already conceded 14 times in 10 games in all competitions this season to raise questions about Mourinho’s defence.
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