Leeds take on old foes United on Wednesday for this first time since 2011.
In footballing terms, the Roses rivalry stretches back to the 1960s, when a tension arose between Leeds’ Don Revie and Red Devils legend Sir Matt Busby as they managed two of the top clubs in the English game.
The Pennines derby continued to intensify over the years, but has diffused more recently with the Whites not in the top flight.
That’s not to say that this week’s pre-season game won’t be anything but ‘friendly’ though, with supporters of the two sides still clearly having a disliking for each other, as revealed by Hernandez.
“Somebody told me, ‘No, no, no, not red here!’”
The former Spain international has never played against United for Leeds.
But he says he got a real taste for just how much disdain there was between the two clubs when he was given a bitter warning about the choice of his shoe colour.
“I haven’t lived these games, but the people tell me some things,” Hernandez said.
“I know this because I remember one day I go to Elland Road with red trainers and somebody told me, ‘No, no, no, not red here!’ so I understand this rivalry.”
Unlike the majority of Marcelo Bielsa’s 16-man squad, Hernandez has played against United before.
The 34-year-old featured alongside current Red Juan Mata in a Champions League clash – with the Whites ace even scoring past Ben Amos.
Hernandez recalled: “Obviously the best memory for me is the Champions League game with Valencia.
“We drew 1-1 and I scored the goal. It was special for me because I’m the only one in Valencia to score in this stadium.”
Hernandez is also looking forward to seeing good friend Mata again when he matches up against him at Perth Glory’s Optus Stadium – and he even has his eyes on nabbing his shirt at full-time.
“When I arrived here, I texted him and he texted me ‘See you Wednesday’,” said Hernandez.
“He told me he wants my shirt and I want his shirt. I have a lot of his shirts, but I want the new one.
“He was my team-mate for four years in Valencia and my room-mate and I’m happy to play against him.”