Ole Gunnar Solskjaer has promised Odion Ighalo will feature against his former side on Saturday.
Defeat to Manchester City on Wednesday meant it was the fourth time United had lost at the semi-final stage of a competition during Solskjaer’s tenure.
But with the FA Cup now thrust upon them the United boss and his players have a chance to move on quickly.
And Solskjaer has confirmed Ighalo, who has only featured a handful of times this season, will play against his old club.
“Odion, it’s special for him against Watford, he will be involved, he’s in the squad,” said Solskjaer.
“He’s been training really well, he was the top scorer in round robin we just finished. He’s not lost any of his quality, it’s been difficult for him to be out of the squad as many times as he has because he did really well up until the summer.
“This season he’s not had as many opportunities and not let himself down as a professional and a human being.
“He’s always a positive influence in the dressing room. Hopefully I don’t need to put him on in that we need goals, but hopefully he can join in.”
“It’s always exciting and hopefully it will be the second time I’ve played against Watford since I left,” Ighalo told Watford’s website. “I can’t wait to see the lads I had such a good time with.
“Me playing for Manchester United today, they saw what I did with Watford in the Premier League, that’s why I have the opportunity to be here today, so my story would not be complete in my career, my life, without mentioning Watford.”
Ighalo’s loan from Shanghai Shenhua will finish at the end of January, and it’s a large reason why United brought in Edinson Cavani.