The Red Devils opted to let both Alexis Sanchez and Romelu Lukaku leave Old Trafford this summer without bringing in any direct replacements.
Rashford started up front in the middle for Manchester United in their 1-1 draw with Southampton at St Mary’s at the weekend after Anthony Martial was ruled out due to injury.
The England international did not have the best of games as the Red Devils were pegged back and held to a draw.
And former Manchester United midfielder Hargreaves believes that Rashford is better suited to playing out wide than through the middle, highlighting the Red Devils’ need to bring in a real number nine.
Speaking in an interview quoted by Metro, Hargreaves said: “It’s a shame because I love him as a player, I think he’s terrific, but they [United] need a No.9.
“Sanchez has gone, Lukaku has gone, they needed him to step up. Martial has really taken the No.9 shirt and been great.
“Rashford had a chance [against Southampton] and he didn’t take it. ‘Is he going to be a No.9, is he going to play off the left? He didn’t capitalise.”
Manchester United have only taken five points from their opening four Premier League games so far this season.
They will attempt to get back to winning ways when they host Leicester City in front of their home fans after the international break on Saturday 14 September.
Manchester United finished sixth and without a trophy last term.
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