He begins with a departure. Billy Gilmour made a permanent switch to Brighton on transfer deadline day, having spent last season on loan at Norwich City.

‘We had high hopes,’ Tuchel begins. ‘He played for us in the first half-a-year when I was at Chelsea and he played some important matches for us, and he looked for a new challenge, which did not go so well for him with Norwich.

‘We expected more and he expected more so without pointing a finger, it is difficult for him and also for us to not play at Norwich, to be relegated, and then suddenly be a central midfielder for Chelsea, competing for top four and for every title. It is a huge step.

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‘So we were looking. The ideal solution would have been maybe that he goes again on loan as the concurrence is huge for us in central midfield and we thought he's not the age anymore where he can live again with five, six, seven or eight matches during the whole season, and fulfil his own potential.

‘So ideally it would have been another loan but Billy did not want to go on loan. It was a no-go for him and so in the end we agreed to a sale.’

Redressing the balance when it comes to the number of midfielders in the squad is the arrival of Denis Zakaria. The Swiss international signed on loan from Juventus and was the last of the new players coming in.

‘This was an option that came in very late,’ our head coach explains. ‘It was related not to the numbers that we should have in midfield but the numbers that we actually have.

‘We have Kova, who had knee problems over the last weeks. He'll hopefully make it without surgery and will be available right now but he was a little bit on the edge of surgery. N’Golo Kante is struggling and suddenly Ruben Loftus-Cheek had a hamstring injury that could have cost us some games. Fortunately he is available this weekend but this was the situation so this [the recruitment of Zakaria] was more or less a last-minute option.

‘He gives us a lot of options because he has speed, height and physicality to bring to this group. He can play in the back-three and I think he can play even in a back-four. He can play both positions in the midfield and maybe even wing-back because he's fast enough and has the volume.’

Tuchel is certainly the man to know the possibilities offered by Thursday’s other signing, Pierre-Emerick Aubameyang, having managed the striker successfully at Borussia Dortmund.

The boss says the pair being reunited started to become a possibility a few weeks ago when Bayern Munich, who had previously turned down Barcelona’s approaches for Robert Lewandowski, allowed that transfer to go through. The previously unlikely scenario that the Spanish club would allow one of their existing strikers to leave now became a reality.

With the deals now done, Tuchel indicates there has been harmony in the club under the new ownership when working through the process.

‘Not at Chelsea but I had it with some signings where I was not involved and I was maybe not 100 per cent agreeing on the potential or on the quality that the player is adding to the group.

‘It is not the case this year which is very good and very positive.’