The Red Devils are believed to be on the lookout for attacking reinforcements in the coming months as they look to bolster their squad following a disappointing season to date.
Sanches, 18, has been heavily linked with a transfer to Old Trafford in recent weeks, speculation that was rife during the January window.
The teenager is believed to have a release clause of around £62m but Benfica are reportedly willing to accept £47m for the midfielder.
And former Manchester United midfielder Hargreaves feels that Sanches would be a good signing for the Red Devils.
Speaking on BT Sport, Hargreaves said: “I’m not sure 60m euros is a gamble.
“The release clause is ridiculous but he’s going to be a super player, no question.
“18-year-old, only played fifteen games so far but he’s got a terrific future ahead of him.
“He’s more of a box-to-box midfielder. Really good passer of the ball. Great striker of the ball from distance.”
Manchester United are currently preparing for their Europa League trip to face Danish champions Midtjylland on Thursday night.
The Red Devils slumped to a disappointing 2-1 loss to Sunderland in the Premier League on Saturday.
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