It was Paulo Fonseca who announced his own sacking shortly after midnight. Driving out of the parking lot at San Siro, he stopped briefly to answer questions from a reporter. “Yes, it’s true, I’ve exited Milan,” he said. “That’s life. Life goes like this. My conscience is calm, because I did everything I could.”

Such phrasing might make it sound as if Fonseca took the decision himself. He did not. Milan eventually confirmed they had relieved the head coach of his duties in an official statement published on Monday morning. They have appointed Sérgio Conceição as his replacement. La Gazzetta dello Sport reported that documents had already been exchanged for the new coach’s contract before the Rossoneri kicked off against Roma on Sunday.

The case for change is obvious. After drawing 1-1 with the Giallorossi, Milan will end the year eighth in the Serie A table. They are eight points adrift of the top four and trail joint-leaders Atalanta and Napoli by 14. Fonseca had raised the bar after he replaced Stefano Pioli in the summer and stated his objective as: “Win the Scudetto.”

But that does not justify treating him so poorly. If the decision to fire Fonseca was made before kick-off, why not inform him before he spoke at a post-match press conference? Barely an hour before he broke the news of his own dismissal, the Portuguese had told a room of journalists that he expected to travel with his team for Milan’s Supercoppa Italiana semi-final in Riyadh on Friday.

It was a damning image, Fonseca sitting hunched and alone behind the big red desk in the interview room, fielding questions from reporters who knew more about his position than he did. A perfect contrast to the photo of him grinning and eating a Christmas banquet with his players, which remained as the banner on the club’s X account right through to late Monday morning.

That was always a fiction. Right from the early days of Fonseca’s tenure there had been signs of disharmony, beginning with Rafael Leão and Theo Hernández’s decision to stand apart from the team while the head coach gave out instructions during a cooling break against Lazio in August. He had sought to send a message by dropping both players from his starting XI, but perhaps he lacked the authority to make such a gamble. Fonseca had landed the job only after supporters rebelled against the club’s first candidate, Julen Lopetegui.

Nobody seemed overly eager to take ownership of the decision. Fonseca got little public support from his board as Milan started the season slowly, winning three of their first nine games. Instead, his influence was contested further by the figure of Zlatan Ibrahimovic, whose role with Milan has remained ambiguous ever since Gerry Cardinale made him an operating partner at RedBird Capital, the investment firm that owns the Rossoneri. After Fonseca remarked in mid-August that Milan had done their transfer business for the summer, the Swede responded that “the manager manages, the club does the rest … the window will close when I say it does”.

It is the board, more than Fonseca, that has been the target of fan protests in recent weeks. As the club celebrated its 125th anniversary before a game against Genoa this month, Ibrahimovic was loudly whistled by fans at San Siro – a sharp contrast to all the other former players being honoured with applause. Cardinale and Milan’s CEO, Giorgio Furlani, were also singled out for abuse. Still, the head coach must take ownership of performances on the pitch. Fonseca arrived promising “offensive, courageous football”. As we close on the halfway point of this season the team are on track to score 18 fewer Serie A goals than they did under Pioli last season despite adding the strikers Álvaro Morata and Tammy Abraham in the summer.

In part, you could chart that decline to the diminished performances of Leão and Hernández, neither of whom have performed consistently close to their best. But Fonseca also stands accused of tinkering too much and denying his team the chance to get into a rhythm.

There were days when it all came together, most notably in a 3-1 win away to Real Madrid and the derby triumph over Inter that ended a sequence of six consecutive defeats to their rivals. That was Fonseca at his bold best, sending out Morata, Abraham, Leão and Christian Pulisic in an effective four-man attack. Somehow, though, Milan always felt fragile. They played some brilliant football again versus Roma on Sunday, taking the lead through Tijjani Reijnders. It could have been 3-0 before Roma scored back in the 23rd minute, after Morata squandering a near-post chance and Hernández came close from the edge of the box.

Yet it could also have been 4-3 to Roma by full-time. Their equaliser was magnificent: Artem Dovbyk turning as if to take the ball past his defender from Niccolò Pisilli’s forward pass but instead flicking it with his heel to Paulo Dybala, who volleyed into the corner. But Roma missed more straightforward opportunities in the second half, when Dovbyk and Stephan El Shaarawy drew saves from Mike Maignan and Eldor Shomurodov hit the woodwork.

Empoli 1-2 Genoa

Parma 2-1 Monza

Cagliari 0-3 Internazionale

Lazio 1-1 Atalanta

Udinese 2-2 Torino

Napoli 1-0 Venezia

Juventus 2-2 Fiorentina

Milan 1-1 Roma

Como v Lecce (Monday, 5.30pm GMT)

Bologna v Verona (Monday, 7.45pm)

Fonseca was sent off for protesting the non-award of a penalty for a challenge on Reijnders just before half-time. He might have had a case. Even a victory, though, would not have saved his job.

In a neat twist, Conceição’s first match in charge – the Supercoppa semi-final – will be against Juventus, whom his son, Francisco, plays for. The older Conceição fits the description that many Milan supporters wanted for Pioli’s successor in the summer: a manager with a concrete track record of lifting trophies. In seven years at Porto he won the Primeira Liga three times and the Taça de Portugal four.

Conceição will have his work cut out, though, taking over midseason in a league that has become ferociously competitive at the top end. None of Atalanta, Napoli, Inter or Lazio will be easy to dislodge from the top four. Fiorentina, Juventus and Bologna all sit between Milan and the Champions League places too.

One step at a time. Milan have at least managed to announce their new head coach without him having to do it himself from the front window of his car.

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