The Red Devils signed the Chile international in a swap deal with Arsenal in the January transfer window as Henrikh Mkhitaryan completed a move to Arsenal.
Sanchez made two assists in his Manchester United debut in a 4-0 victory over Yeovil Town in the FA Cup third round back in January.
The South American forward scored his first Red Devils goals in a 2-0 win over Huddersfield Town in the Premier League earlier this month.
However, the Chilean star has struggled to have an impact on the Manchester United side in their last three games in all competitions.
Indeed, Jose Mourinho appears to be struggling to work out where to start his January signing in his inconsistent Manchester United team.
Former Manchester United midfielder Scholes believes Sanchez should be used on the left hand side of the Red Devils attack.
“I think he fits in best on the left-hand side,” Scholes told BT Sport. “That’s where he’s played his best football throughout his career, whether it be at Barcelona or Arsenal.
“I think the problem the manager has at the minute is that four of his forward players want to play on the left-hand side.
“Lingard, Martial and Rashford would like to play there as well. But Sanchez does all his best work from there.”
Manchester United were 2-0 winners at Huddersfield Town in the FA Cup fifth round at John Smith’s Stadium on Saturday evening.
The Red Devils will make the trip to Spanish side Sevilla in the first leg of their Champions League last-16 clash on Wednesday night.
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