The Red Devils started their week with a 2-1 defeat by Sunderland at the Stadium of Light before Danish champions Midtjylland were 2-1 winners against United in the Europa League.
Unsurprisingly, Van Gaal is facing an uncertain future at Old Trafford following a disappointing run of results.
However, former United midfielder Hargreaves believes the 20-time English champions’s signings are to blame for their poor results over the past three years.
Hargreaves told BT Sport: “You can’t blame those errors on Louis van Gaal. Before Van Gaal everybody blamed David Moyes. I don’t think that the team is in a position where they can compete to win the Premier League and the Champions League.
“The club needs to look at itself and its recruitment.
“It is easy to blame the manager but you can change the manager, but the players will still be there next season. Man Utd used to have the best players in every position.”
Van Gaal signed Memphis Depay in a £25m deal from PSV Eindhoven last summer. The Dutchman also signed Bastian Schweinsteiger, Morgan Schneiderlin, Matteo Darmian and Sergio Romero.
The Red Devils take on League One side Shrewsbury Town in the FA Cup fifth round on Monday night.
United have lost their last two games in all competitions following defeats by Sunderland and Midtjylland.
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