Julen Lopetegui will make it to the clásico between Barcelona and Real Madrid at the Camp Nou on Sunday but, for the first time in more than a decade, Lionel Messi will not – and nor will Cristiano Ronaldo. This is the Madrid manager’s 137th day in charge and, whistled on Tuesday night after his team finally broke a five-game winless run, it could also be his last.

Asked on Tuesday if their coach would still be on the bench for Sunday’s game, Madrid’s director of institutional affairs, Emilio Butragueño, mumbled “yes, yes”, despite having just witnessed an unconvincing 2-1 win over Viktoria Plzen.

Real Madrid, Julen Lopetegui and the actions of a condemned man | Sid Lowe Read more

When Lopetegui gets to the Camp Nou, sitting in the front row of the stand just behind him is likely to be Messi, wearing a sling on the arm he broke a week ago. When he went down last Saturday against Sevilla, the stadium fell silent. It took nine minutes to make the change, partly because Ousmane Dembélé was slow, but more because Messi, who had scored one and provided another, wanted to continue – as did everyone else. Madrid were eight days away and Messi does something to them no other player ever has: all-time clásico top scorer, leading an unprecedented domestic dominance, he has a tremendous intimidatory power. But on Saturday the squad was named and Messi was not in it.

A blunt truth: Madrid have missed Ronaldo and Barcelona know they will miss Messi. It is true that at this stage last season Ronaldo had scored only one league goal and that last month Madrid played wonderfully without him against Roma. The focus had, it was said, become more collective. They pressed higher, sought possession – achieving 71.2% at home, more than Barcelona – and it appeared an opportunity for others, Gareth Bale and Karim Benzema particularly.

Bale has some record at Madrid: 200 games, 92 goals, 62 assists. But another statistic concerns: while he has played in 200, he has not played in 103. He began this season with responsibility but Madrid’s form has slipped. Luka Modric and Toni Kroos have not found their feet; defensively, the team have been dreadful, Sergio Ramos especially; Benzema’s evolution into a No 9 again is not complete, and nor is Bale’s evolution into a leader. Madrid went five games without scoring. Lopetegui bemoaned misfortune but there was more, and it brought the head coach to the edge of the abyss.

Lose on Sunday and Madrid would be seven points behind Barcelona; win and they would be only one point off – and favouritism so rarely plays out the way it should.

Defensively vulnerable, Barcelona have not always impressed either and losing Messi is huge. Asked if his absence conditioned the team, Ernesto Valverde replied: “Not at all ...” and then laughed: “We have to accept it. It doesn’t bring me out in a rash to hear the word ‘Messidependency’.”

In November 2015, injury forced Messi to start on the bench at the Bernabéu: by the time he came on, Barcelona were 3-0 up, but they had Neymar then. Now the nearest thing is, in theory, Dembélé, signed with the Neymar money. But there are doubts about his adaption, commitment and play. He has given the ball away 165 times this season. Dembélé was poor after coming on against Sevilla and did not feature against Inter on Wednesday when Barcelona were superb, Arthur, Ivan Rakitic and Sergio Busquets taking control.

Ahead of them was Luis Suárez. Always analysed through goals and work, it is time to take in his passing and vision. He has four goals and six recorded assists, which doesn’t include the two dummied “assists” against Tottenham. “I’ve been against him before and whenever the coach took him off I practically gave them a hug,” Valverde says.

Every season, Suárez has scored against Madrid: six goals in 10 games. To his left Jordi Alba is zooming up the wing, legs whirring. Some are starting to liken Arthur to Xavi. Oh, and Marc-André ter Stegen to Superman.

Sign up for our daily football email, The Fiver.

Madrid have Bale, Benzema, Modric, Isco, Marco Asensio and, having appealed a red card received playing for the B team, Vinícius, too – an 18-year-old Brazilian more central to Lopetegui’s troubles than it may appear. There is talent there. Loads of it. There always is. This game remains the biggest in the world, and by a long way. And yet there is something missing, a reason why there may be a hint of nostalgia, melancholy about this match – a glimpse of a future, everyone’s mortality. Messi is 31 now.

It is 11 years since a clásico without Messi or Ronaldo. Between them they have played 68 clásicos and only Messi has scored more clásico goals than Ronaldo, as if it’s just the goals anyway. Even in a history as rich as this rivalry has, they marked an era, this generation forever theirs. Managers come and go, and no one knows that like Lopetegui, but it had started to feel like, somehow, they were always there. Until now.