Chris Smalling and Victor Lindelof will be forming the centre-back pairing for the trip to Hertfordshire.
Mourinho joked about this when defending his deployment of the player.
Romelu Lukaku and Chris Smalling scored within three minutes of each other in the opening period, with Andre Gray netting in the second half for the Hornets, but they could not maintain their 100 per cent start to the season.
"Marouane is giving us more than that, he is giving that but also quality and simplicity".
"We have to remember that Harry Kane at that age had hardly played anywhere near the matches for Spurs", he added, emphasising that Rashford is yet to reach his full potential and will continue to improve.
Tongue in cheek, Mourinho said he is still expecting criticism when the forward was not in the team against Watford.
"He's playing simple and well".
Jose Mourinho's men will now travel to Young Boys in the Champions League on Wednesday in buoyant mood before hosting Wolves on Saturday.
"I don't know if that is true", said the United manager when asked whether Raiola was trying to force a transfer to Barcelona. The only thing that is clear for me is that the player never - never, in all these days we are together - told me that he wants to leave.
Determined defending from Craig Cathcart and Christian Kabasele, who made last-ditch tackles to deny Sanchez and Anthony Martial respectively, kept Watford in the game right up until the death, and Matic's second booking for wiping out Hughes gave them a little bit more hope in the final minutes. "We gave them the chance to be reborn, score a goal and give us a hard match".
"So I can only comment on what is real for me, not in what I read, not in what I listen to".
Watford had won their four previous league games of the season heading into this clash - but even in defeat manager Javi Gracia felt his players showed their class.
"I think the first half, they played much better than us".
"If you don't mind losing a couple of minutes, I'm going to do something not for you [the media] but the United fans and I think I hold myself to the United fans and for them I am going to spend two minutes with you", Mourinho began.