Former Manchester United striker Andy Cole has admitted that there is "a big gap" between the Red Devils and Real Madrid as Jose Mourinho's side look to make an impression in the Champions League this term.
Last season's Europa League victory saw United secure a return to the Champions League, and the 20-time English champions will open their group-stage campaign against Basel after the international break.
Real Madrid are the holders of the Champions League title after retaining the crown last term, and Cole has claimed that his former club still have a lot of work to do in order to match up to the Spanish giants.
"It's massive for the club [to be back in the Champions League], because that gives you another platform to bring in the players that you need," Cole told reporters.
"That is what the fans want and what they expect at a club like Manchester United. So that is major as well. It gets tougher and tougher to win that Champions League. If you look at the team that has won it two years on the bounce now, we played them in the Super Cup and I think you saw the gap there.
"There was a big gap between Real Madrid and Manchester United. And Real Madrid had some of their better players on the bench as well. So to win that competition you are going to have to be in tip-top condition."
United have won their opening three games of the new Premier League campaign without conceding a goal.
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