The Football Association refused Villa's request to postpone their third-round clash against Liverpool despite boss Dean Smith and his first-team squad having to self-isolate after 10 players tested positive for COVID-19.
With Villa's training ground closed, a team comprised of Under-23 and Under-18 players were beaten 4-1 at home and as the situation showed only slow signs of improvement, the club asked the Premier League to rearrange Wednesday's match at home to Spurs.
The League agreed and on Monday afternoon -- just over 48 hours before kick-off -- it confirmed in a statement that Spurs would instead play Fulham, a match already pushed back from Dec. 30 due to another outbreak.
Fulham boss Scott Parker labelled the late alteration as "scandalous" but Mourinho believed the bigger issue is consistency in determining the infection rate required to postpone a fixture.
Typically, a team will be ordered to play a fixture if they have at least 14 players available, but clubs have been able to argue their specific circumstances on a case-by-case basis.
Mourinho said: "Look, since preseason when I was told that if you have 14 players available, you play football, since that moment I thought 'we are going to play, we are going to end the season and we are not going to have problems.'
"That rule, if you can call it a rule, for some reason changed and we had some matches postponed. Since that moment, the situation became a little bit more difficult. And then, we need leadership, we need decisions to be made and if we all are very selfish or if we all want the perfect situation for ourselves, it is going to be very difficult for the Premier League to make it amazing for everyone. That's obvious.
"I can also say, 'why Aston Villa played Liverpool in the cup and Aston Villa doesn't play against me tomorrow?' Of course, Aston Villa has very good young players and they played a beautiful game against Liverpool but I would love tomorrow to play against that Aston Villa. Why I don't play? And you want me now to be crying about that?
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"I'm not crying about that, I'm crying about 'we cannot have more matches postponed.' We can't. The team in the Europa League is impossible to have more matches postponed so if tomorrow, we don't play against Aston Villa because Aston Villa has, let's say, half of their team with coronavirus, if we cannot play against Aston Villa, which I accept, the same way I was not happy but I accept not to play against Fulham in the past week, come on.
"Tomorrow, we need to play, If it is not Fulham it is somebody else but we need to play a match. We cannot have more matches postponed."
Mourinho had been critical of the Premier League's decision to postpone Tottenham's original game with Fulham just two hours before kick-off, a complaint Parker described on Tuesday as "irrelevant" on the basis he was able to plan for that fixture in a way the Cottagers have not been able to this time.
They have also had their home game against Chelsea moved back from Friday to Saturday evening while Parker has claimed he may have picked a different team for last weekend's FA Cup third-round extra-time win at Queens Park Rangers had the fixture been in the schedule.
But Mourinho even suggested Fulham should "apologise" if they arrive at the Tottenham Hotspur Stadium with their strongest lineup.
"In relation to Fulham, I think we should wait for tomorrow," he said. "We should see their team, their starting lineup, their bench and the players that are not involved in the game.
"After that, we can all feel sorry for them or we can think that they shouldn't speak. My feeling, it is just my feeling, is that they will play with everybody. Maybe one player out, maximum two. That is just my guess.
"As you know, all this [COVID testing] is confidential information and of course we don't have access to any of this information. It is just a feeling that I have, the best Fulham will be here tomorrow. When we see the best Fulham, then you realise that lots of things, they don't make sense.
"Do you want to finish this season or no? Do you want football to keep going or no? Do we want to be the only country in Europe without football or no? Do we want the end of the season with a champion with a cup winner, with relegation with Europe or we don't? That's the main question. Do you football journalists want to keep working or no? Do we want to have our salaries? Yes or no. What do we want?
"We played, if I'm not wrong, 11 more matches than Fulham, since the beginning of the season. Eleven. We played every week, three matches per week. We played in one week, four matches.
"They played Saturday against QPR in London. They have Sunday, Monday and Tuesday to prepare for the game tomorrow. If tomorrow they come with half of the team, I will be the first one to apologise to them and I will be the first one to say we played this game with an advantage.
"If tomorrow, they come with their best team, I think they should apologise to all of us. Come on, let's play football, let's behave the best we can, let's protect our industry, our image, and let's play football."