United hold a 1-0 lead ahead of the second leg at the Emirates Stadium on Tuesday.
“If we play to the ability we did in the first half last week we will have no problems,” Giggs is quoted as saying by The Sunday Sun.
“We went out to get the crowd going and play at a quick tempo. That is what we do when we are at our best.
“Arsenal are a top team and they are capable of scoring goals so we are under no illusions about how difficult this is going to be.
“But our form in Europe has been excellent and we are in a good position.”
“You have to look after Arsenal’s quality players,” he added. “They have so many match-winners; [Cesc] Fabregas, [Emmanuel] Adebayor, [Theo] Walcott, [Robin] van Persie, if he is fit. The threat is obvious, so you have to try and nullify it.”