Leeds were hit for six in December's reverse fixture against their arch rivals at Old Trafford as Ole Gunnar Sollskjaer's side recorded a 6-2 victory.
"For us, we know it's a massive game," Harrison told Sky Sports.
"We know we have to redeem ourselves for last time.
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"But also there's a lot of history and emotions behind this game as it is anyway because of the rivalry and how much it means to everyone associated with the club.
"We are going to do all we can to try and create some happy faces today but we know it's going to be a tough game."
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Thank you Laura Collins