For a moment, Rubén Amorim's easy smile disappeared and his eyes narrowed.
'New system? Are the wolves playing with a new system? Amorim responded to his inquisitor in the Molineux press room.
'They played with the same system and Vitor Pereira used the same system in Saudi Arabia. Wolves are a completely different situation. The team was formed for this system.'
Late on Boxing Day, and perhaps for the first time, we saw the tension over Amorim beginning to show.
Manchester United's new Portuguese manager had just suffered his third consecutive defeat and took issue with the suggestion that Wolves' new Portuguese manager had succeeded in a week where he struggled in two months at United.
As Pereira finished his first home game orchestrating the cheers of the Molineux crowd with his fists raised, Amorim squatted on the touchline and his team took a knee once more.
Ruben Amorim began to show the strain of trying to turn around Man United after their defeat to Wolves.
Amorim's team fell comfortably at Molineux and recorded their eighth league defeat of the season
United now sit 14th in the table, the same position the club occupied when Erik ten Hag received his exit permit.
On the journey back to Manchester and his home in the south of the city later in the afternoon, he will have had plenty of time to reflect once again on the magnitude of the job he has taken on.
United sit 14th in the Premier League, the same position as when they sacked Erik ten Hag at the end of October, and show no signs of improvement. In any case, the only movement seems to be backwards.
Monday's game against Newcastle marks the halfway point of the campaign. This isn't a slow start or a mid-season problem. If United are not careful, they will face a relegation battle.
At 39 years old, Amorim is a young coach but he has been in football long enough to know the consequences of failure.
Dan Ashworth, one of the men who flew to Portugal to negotiate his move to Old Trafford, has just been sacked as United's sporting director after 159 days in the job. Sir Jim Ratcliffe and Ineos have made the brutal decision to lay off a further 250 employees. Another one wouldn't hurt.
Amorim's replacement at Sporting Lisbon, Joao Pereira, was fired on Christmas Day. This is a cutthroat industry and he knows it.
He also knows better than to look at social media where mischief-makers revel in United's misery. Rubén Interim, they have started calling him.
“I know the business I'm in,” he said. “The Manchester United manager can never be comfortable, no matter what happens.
Sir Jim Ratcliffe has not shied away from making difficult decisions since taking control of United's football operations.
Dan Ashworth was part of the delegation that traveled to meet Amorim before his appointment and has since been fired.
Meanwhile, Joao Pereira, Amorim's successor at Sporting, has suffered the same fate
“I know that if we don't win, regardless of whether they pay the buyout or not, I know that all the coaches are in danger.”
It seems ridiculously early to even consider such a conversation, but the issue he questioned at Molineux raises a more sensible debate.
Wolves played a back three under Gary O'Neil and, in Pereira, they have appointed a like-minded coach.
Amorim shares the same philosophy and Liverpool's insistence on maintaining a back four was one of the reasons for ruling him out when they appointed Arne Slot.
With Amorim, it's 3-4-3 or nothing. He has made it very clear since he arrived at United and you have to admire this man's principles.
United, on the other hand, equally insisted that Amorim take charge mid-season rather than in the summer, as he would have preferred.
So in November he parachuted into Old Trafford and a growing crisis to make repairs and introduce a system that was foreign to most of his players. In retrospect, perhaps it would have been wiser to wait.
The transition was made even more difficult because Amorim had little time to work with them on the training ground due to the tight match schedule.
Liverpool ultimately opted not to sign Amorim last season due to his commitment to a back three and instead signed Arne Slot.
Despite a shaky start, Amorim has remained admirably persistent in its defensive reshuffle.
The result? A coach who won 16 of his 17 games in Portugal this season (he tied the other) has lost half of his first 10 games in England.
He has talked about literally walking players through his steps at Carrington to get them up to speed; It is an incredible scenario considering that these are experienced international footballers who should not need care during a tactical change.
When Mason Mount suffered another injury in the Manchester derby, Amorim sought some solace in the fact that Mount's time on the sidelines could be spent “teaching Mase how to play our game”.
On Thursday night at Molineux, Amorim estimated that he had only had four training sessions with his players. So is that why you wanted to delay joining United until the end of the season?
“I already knew it was going to be difficult,” he responded. “You hope to win more games, have players with more confidence to sell the idea and work and improve things.
'Right now it is very difficult. “We have to survive to have time and then improve the team.”
Of course, Amorim's philosophy doesn't begin and end with a back three. These are full-backs, which means the wingers have to learn to play more narrowly; a lot of pressure and “running like mad dogs”, as he says.
For a club built on a tradition of wingers, and with quite a few of them in the poor squad he inherited from Ten Hag, it has been a difficult adjustment.
Amad Diallo is one of the few United players who has thrived amid the tactical reshuffle
However, the Ivorian has largely proven to be the exception, with players such as Marcus Rashford not benefiting from the move.
Some, like little Amad Diallo, have prospered. Others, like Marcus Rashford and Alejandro Garnacho, have not.
Both were ruled out for the derby. Rashford has already been left out of the last four games. Garnacho has come back in the last three, but only on the bench.
Amorim arrived with a reputation for being a shrewd manager, but behind his smile an iron will is clearly visible.
There's also a fine line between establishing authority and cutting off your nose to spite your face. Ten Hag did well with his handling of Jadon Sancho. He also had a fragile relationship with Rashford, who frustrated him greatly.
Amorim has taken an even firmer stance on Rashford and should be applauded for that. But the longer a player stays off a losing team, the more useless he becomes.
If Amorim can't get a tune out of Rashford, he can at least get a decent price for him in the January transfer window, and there's no point in having him sitting at home.
Therein lies another problem for the new head coach: United will have to sell to buy the players they want to best suit their system after £600m of spending under Ten Hag left the coffers empty.
There will be no quick fix. Amorim will stay with the majority of this team for the rest of the season and some time to come.
But change will take time, especially given the extent of activity needed in the transfer market to attract suitable players.
To be fair, it's gotten ahead of itself. No question has been dodged and no answer has been falsified. Things are bad at United, he says, and they will get worse before they get better, especially as there are trips to Anfield and the Emirates after Newcastle arrive at Old Trafford.
Amorim has accepted the blame for the results and even United's set-piece problems, having taken those responsibilities away from Ten Hag's man Andreas Georgson and given them to his Portuguese assistant Carlos Fernandes.
He has been surprisingly honest about the anxiety in his team that runs through Old Trafford.
“We have to expect that any play by Newcastle near our area will make the stadium nervous, and our players have to deal with that,” he said before Monday's game.
By then, the bottom six may have edged a little closer to United's shoulder.
More optimistic fans would argue that a couple of wins would propel their team to the top of the table. Wait a month or two and this might all seem like a bad dream.
For now, however, the nightmare scenario for Manchester United and Amorim looms large.