Manchester United could be about to receive an era-defining bid for one of their star players in the upcoming transfer window. This summer Old Trafford is expected to see a flurry of transfer dealings this summer as Sir Jim Ratcliffe looks to rebuild Manchester United. This could include the departure of several current stars on expensive wages. Marcus Rashford falls into this category as he has failed to justify the reported wage of £300k-a-week he received upon signing his new contract last year after a 30-goal season. Rashford has shown moments of his brilliance this season but at 26, you’d…