Christian Pulisic will miss the game after testing positive for Covid-19 earlier in the week. However, the boss hinted that Romelu Lukaku could be in line for his second Chelsea debut after a strong week of training, while Hakim Ziyech and N’Golo Kante have both been training in recent days and could return after missing the Premier League opener against Crystal Palace.

‘With Christian, it’s unfortunately very easy to explain,’ said Tuchel. ‘He had a positive test and needs to follow the protocols so he won’t be available for the game.

‘Hakim and N’Golo were both in training today and they had no problems. We need to have a more intense session tomorrow with them and the team before we decide but right now it seems positive that both can be in the squad for Sunday.’

For Ziyech in particular, it was a cruel injury blow suffered in the Super Cup, curtailing a promising pre-season campaign and a goalscoring contribution in Belfast. While Tuchel is pleased to see the Moroccan back in training, he offered a word of caution about rushing the forward back too quickly.

‘He was very promising in pre-season and had some very good matches last season but also some difficulties and hard decisions for me to take,’ he added. ‘He has been impressive and his attitude has been absolutely right to grow and to show personality.

‘He was decisive in every single friendly game we played and also in the final against Villarreal so it was very unfortunate that he got injured. Now we need to take care of him because on one side we are very happy that he’s back in the pitch but with a shoulder injury it can be a bit tricky.

‘Tomorrow is a decisive training session for him where we will see how far it can go and how much sense it makes. The good thing with a shoulder injury is you can still run and keep your fitness so you don’t lose too much of that.

‘He has many training sessions in his legs so once he gives the green light and feels totally free then hopefully he can find his performance from this season very quickly.’

Ten years on from his first appearance for the Blues, Lukaku is back and looking to hit the ground running at the Emirates. After a positive week of work at Cobham, the signs are looking good that the Belgian will feature against the Gunners.

‘We have one more training session to go but the week was a heavy load for him because he was in the group with the late starters from our guys so it was an overload week so far,’ added the boss.

‘Today [Friday] was lower intensity and tomorrow we have important training for the match but we are hoping he will be on the pitch for Sunday and things look like it.’