'Come on! Quickly... let's do this,' Mats Hummels is in a hurry to leave the BayArena but he will not duck some questions.

Friday evening in Leverkusen had not proven to be the happy send-off to Russia that Germany had been expecting. Though they beat Saudi Arabia 2-1, their performance was underwhelming and the atmosphere inside the stadium was strained for much of the second half.

The tetchiness, in part, was down to the laboured way the 2014 Weltmeisters went about their business. They could easily have been left red-faced and had it not been for a dramatic goal-line tackle by Hummels deep into injury time, Saudi Arabia would have drawn.

Mats Hummels admits Germany must improve if they are to retain their World Cup crown

But there was also anger when Ilkay Gundogan brought on as a substitute; the Manchester City midfielder and Arsenal's Mesut Ozil, both of whom are of Turkish heritage, had a meeting and were photographed with Turkey president Recep Tayyip Erdogan at time when political tensions are high.

Ozil looked furious when he emerged from the dressing room area, refusing to speak. Gundogan, meanwhile, politely declined all invitations to stop and talk. It had been left, then, to men such as Hummels and Manuel Neuer to confront the subject.

'I was not happy with the booing and I hope that it is not going to continue for much longer,' Hummels told the German media.

'When they started, they stopped supporting the other players. It seemed like everyone waited for Ilkay had the ball to boo him.'

So this was the backdrop to our conversation. It was clear that Hummels' mind was racing and plenty of other players would have scuttled through the nearest door when asked to do one more interview but the Bayern Munich totem was prepared to speak to Sportsmail.

Hummels' (C) goal line clearance prevented Saudi Arabia equalising at the death in Friday

Hummels is an engaging character, the type of person who only needs a few moments to make a point, so it was intriguing to get his views on Germany's performance. This success may have been their first of 2018 but nobody was smiling.

'We made it more difficult than it needed to be,' said Hummels. 'We had a good start in the game, we had good control but then we started to play with too many mistakes. We gave the ball away too many times in situations where we didn't have to. We need to be more dominant on the pitch.

'It was similar to the last two games of the season for Bayern, against Stuttgart (lost 4-1 at home) and Eintracht Frankfurt (lost 3-1 in the DFB Pokal final) where lost balls cost us two games. I know the situation and this is what we have to focus the most on.'

But this is Germany, whose record at the World Cup since 2002 reads: finalists, semi-finals, semi-finals, winners. They won the Confederations Cup 12 months ago, too, and many regard them as Europe's outstanding candidates in Russia. The phrase Turniermannschaft - tournament team - was coined for them.

The defender says 'We gave the ball away too much... we need to be more dominant on pitch'

Germany's preparations have been far from their usual high standards and almost chaotic

'It is possible (we will be ok) but it is not something that comes by doing nothing,' Hummels countered. 'We have done it often in the last years, of course, but we cannot wait for it. We have got to make it happen. Yes, we are one of the teams that can win it.

'But every team can win it. You remember Greece (at Euro 2004), don't you? England are improving. They are a good side and they have a really good chance. It's not just because I am talking to you. If someone asks me in private, I tell them the same. France, Brazil, Spain, England, Argentina... these are the top teams.'

Joachim Low must have a top team if he can be without some of Leroy Sane's gifts but the shock that has been felt in England about his omission, is not the same as it is in Germany. Furthermore, there is no sense from Hummels that the PFA Young Player of the Year has been treated harshly.

Hummels claims Leroy Sane will be back and improve for Man City and the national team

'We know he is a very good player and he had a great season with Manchester City,' said Hummels, one of the veterans of the 2014 campaign in Brazil. 'Circumstances are not always easy for the young players - in the games he played there were a great number of changes.

'And for the national team, he didn't play as good as he did for Manchester City until now. He will improve, both with the national team and with City in the coming years. I know myself that sometimes it takes some time to transfer the things you do for your team to the national team. That's just how it is.'

Sane is for the future but the present is Russia and the younger winger cannot help. This is the moment for Hummels and Company to step forward when they open up against Mexico in the Luznihki Stadium next Sunday. Can they be back their on July 15?

'If we want it, we have got to work for this and we have got to focus,' he said before disappearing into a waiting elevator. 'This was the last test before Russia. If we want to win something at the World Cup? We have got to improve. A lot.'