Sheffield Wednesday will be aiming to extend their unbeaten Championship streak to eight matches when they welcome Sheffield United to Hillsborough on Monday evening.
The midweek victory over Brentford has left the Owls six points adrift of the play-offs in 12th position.
Fox, who is set to be available for selection after missing the last two matches because of a back problem, said: “Everything goes out of the window with this game. We’re ready for it and looking forward to it and ready to fight on the night."
Should Fox be passed fit to play and given the nod at left-back, it will be the third time he has lined up against United. Fox has started the last two derbies, including the goalless draw at Bramall Lane last November.
"I played in the one earlier this season," said Fox. "We were going through a tough time and we just said let’s forget about everything and put everything into this one game.
"We took a point at the end of the day and it’s what we needed. It was a great occasion and the atmosphere was great too and we’re expecting the same again next week."
The former Charlton Athletic player believes there is "pressure on both teams" to pick up maximum points in front of the TV cameras. A third consecutive win would boost Wednesday's faint play-off hopes while United are pushing for automatic promotion.
There is a lot riding on Monday's tussle. As an occasion, it will not be for the faint-hearted. But Fox says he cannot wait.
He said: "It’s what you grow up wanting to do; you want to play in the big games in front of big crowds. The atmosphere will be amazing and growing up that’s all you want to play in front of."
Fox and Owls team-mate Steven Fletcher visited Weston Park Cancer Charity earlier this week. The pair are ambassadors for the charity, which raises funds for Weston Park Hospital.
A bucket collection will take place around Hillsborough on Monday to raise cash for the charity and both the Owls and the Blades players will wear warm-up t-shirts to show their support.
“It means a lot to visit Weston Park," said Fox. "I’ve had illness in my family, so to give back to the community as well and put a smile on people’s face is what we want to do.
"We came down at Christmas and saw the work that everyone puts in and it’s massive for everyone. They cover such a big area so to get that publicity that comes with the derby game can only be a good thing.
"It’s a big eye-opener, and that’s what we do these visits, the boys like doing it because it puts smiles on faces."