United left Catalunya with a 0-0 draw and a fine chance of progression to the final of the Champions League, providing that they can manage a goal at Old Trafford.
Hargreaves explained that this was the plan all along.
He told MUTV, "I think we’d have taken a 0-0 before the game. Defensively I thought we were strong and didn’t allow Barcelona any clear chances.
"They had a lot of possession and kept the ball well, but they didn’t really penetrate us and that was the strategy going into the game."
It might have all been so different had Cristiano Ronaldo netted his side's second-minute penalty.
But the ex-Bayen man countered, "You’re not going to score them all.
"He’s scored more than he’s missed and I think maybe he changed his mind at the last moment. It probably would have changed the flow of the game had we scored, but it’s fine."
There was another 'penalty' incident later when Rafael Márquez appeared to bundle over Ronaldo in the box, but referee Massimo Busacca waved away any protests.
Hargreaves concluded, "“It looked like a penalty but after the referee had given one penalty, it would have been brave for him to give another and a red card."
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