Leicester City manager Claude Puel said it 'is difficult to manage' the tension in the Foxes squad between Owls fan Jamie Vardy and former Blade Harry Maguire.
Jamie Vardy tells Harry Maguire - 'You're either Sheffield Wednesday or Sheffield United ... you can't be both!'
The Frenchman made the tongue-in-cheek quip during a press conference ahead of Sheffield United's trip to the King Power Stadium on Friday night.
Puel said: "Sheffield United is a former club of Harry. Sheffield Wednesday was former club of Jamie. It is difficult to manage this in the squad!"
Maguire made 134 appearances for the Blades before joining Hull City in the summer of 2014.
The England international defender joined the Foxes last summer in a deal worth £17 million.
“When I was a young boy, my dad supported Sheffield Wednesday and my mum supported Sheffield United,” Maguire told the Leicester Mercury.
“When I was around 10 years-old, my dad used to take me to a couple of games but ever since I played for Sheffield United [I’ve supported them], I’ve played for them when I was 11 years-old.
“I was a ball boy week in, week out at Bramall Lane from when I was 14 until 16 or 17. Then, I broke in and made my debut. I definitely follow Sheffield United now. It’s a great club and I thank them a lot because they’ve done so much for my career.
“I joined when I was 11 years-old and it was great time for me. I came across some great coaches who brought me on leaps and bounds. I’ve learnt so much from them.”
Owls fan Vardy was released by Wednesday as a teenager and after spending his early career in non-league and the lower reaches of the football league he signed for Leicester in 2012.
He has scored 75 goals in a 194 appearances for the Premier League side.
At yesterday's press conference City boss Puel vowed to field a strong side in the FA Cup clash against Chris Wilder's Blades.
He said: "
“We want to get as far as we can in the cup and it will be a strong team, like the last was.
“Many teams can win the cup, of course it is a tough competition and the next game against Sheffield United they will be tough.