The Daily Mail says Varela impressed in United U21's 4-1 win over Bolton Wanderers.
Varela, a £2.5million summer acquisition, offers pace, movement and an attacking thrust from full-back, constantly overlapping and worrying opponents but the defensive side of the Uruguayan's game requires some polish.
Varela was left with twisted blood and stretched sinews after a troublesome first-half that saw him regularly outpaced and out-thought by Bolton's excellent Tom Youngs.
The Uruguayan only appeared more comfortable in the second-half when liberated from defensive responsibilities and allowed more freedom as he was pushed forward to right midfield.
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