The Portuguese’s side, looking to defend their title this time around, have already claimed comfortable wins over Reading and Wigan Athletic.
Man United will travel to Ewood Park on Sunday for a fifth round tie against Blackburn Rovers.
And Herrera, speaking earlier this week, noted that there is a real desire to pursue the FA Cup amongst United players this season.
“It’s a massive competition,” he said. “When some teams rotate players, that doesn’t mean they don’t give importance to the FA Cup.
“It’s the oldest competition in England and I think it’s the most amazing cup in the world because of the organisation. For me, the organisation in England is fantastic. The last four play the semi-final one game and then the final at Wembley too and it’s fantastic for the fans.
“Every club wants to win the FA Cup, teams not in the top six even more as they can get in the Europa League [through winning it]. So it’s a fantastic competition to play in. We want to keep playing in it and win away against Blackburn.
“We have very good memories from last season and I’m very optimistic because we have a very good squad.”
Last season’s FA Cup adventure reminded supporters of what the FA Cup, whilst unavoidably decreasing in value, can still produce – that carnivalesque, curtain-coming-down-on-the-season atmosphere was still there when United descended on the Wembley turf against Crystal Palace back in May.
Supporters, this time around, will hope that a promising cup run is not the zenith of United’s season. That said, this competition provides a completely different dynamic, and Mourinho – currently planning for Wembley final later this month – will want to take full advantage.