United secured a precious away win at Stamford Bridge last week in the first leg of their Champions League quarter-final with Chelsea despite only having 46% of the ball. It follows a trend started by Inter Milan last term, who were content to let Barcelona pass the ball around during their semi-final but denying them any space to exhibit their attacking skills.
At Old Trafford, United would normally be expected to take the match to their visitors. But Park has warned Red Devils fans that might not necessarily be the case, and said: "Possession is not important. What is important is how many chances you create, or how many shots on target you have."
He added: "The other team having the ball in front of us is not a big problem. We just watch and wait.
"If we press, then get the ball, we can play on the counter-attack."