Sérgio Conceição said last week that he was sick and tired of this transfer window. “A month is far too long,” he argued. “It has not been positive on an emotional level for many of our players.”

The counter-point arrived in the Milan derby on Sunday night. Starting at right-back for the Rossoneri was Kyle Walker, signed on loan from Manchester City a fortnight after he had informed the Premier League champions of his desire for a move. He was outshone on his debut by the man inside him at centre-back, Fikayo Tomori, who has spent this entire window being linked with transfers elsewhere.

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First came the offer from Juventus, a €5m loan deal with an obligation to buy for €25m more in the summer. Accounts varied on whether Tomori rejected that move or Conceição blocked it, not wanting to strengthen a rival for Champions League qualification. In any case, Tottenham sought to capitalise with a bid of their own. Milan accepted, but the player said no.

Tomori has always been delighted to play for Milan. He told ITV in December that joining from Chelsea in 2021 had been “the best thing I ever did and the best decision I made, not only in football but in life”. He has 164 appearances for the and was a key figure for the side that won Serie A under Stefano Pioli in 2022.

Yet his performances have been on a downward trajectory since. There was a slight decline in the season that followed the Scudetto and a much more pronounced one last term, Tomori making fewer tackles and more positioning mistakes.

The trend had continued in this campaign. Against Fiorentina in October, Tomori misjudged a long ball from the goalkeeper David De Gea, leaping at nothing and allowing Moise Kean to steal in behind and set up Albert Gudmundsson’s winner. Days earlier, Tomori had been caught ball-watching as Milan conceded the only goal of their Champions League defeat to Bayer Leverkusen.

How to explain this apparent decline of a player who only turned 27 in December? He is hardly the only Milan player to take a step backward in this period, for which successive managers share a part of the blame. Pioli’s relationship with his squad deteriorated, while Paulo Fonseca never even built those connections.

Tomori was also sidelined for two months by a hamstring tear last season, another casualty in what has felt like a never-ending defensive injury crisis. Pierre Kalulu, a fellow mainstay of that title-winning team, missed 39 games in 2023-24 and then joined Juventus. Strahinja Pavlovic was signed to replace him but competition for playing time with Matteo Gabbia and Malick Thiaw has denied any of them a chance to form settled partnerships.

It is too soon to speak of Milan’s tactical identity under Conceição, who has switched between 4-3-3 and 4-2-3-1. He has talked about wanting to activate a more active press but against Inter on Sunday, his team often fell into a lower block. It was effective for much of the first half, Hakan Calhanoglu struggling to pick through a crowded midfield.

Yet Milan’s goal came from the sort of forward harrying that Conceição has encouraged. Tammy Abraham, the third Englishman in Milan’s starting XI, picked Calhanoglu’s pocket and exchanged passes with Ismaël Bennacer, who released Theo Hernández down the left. He fed Rafael Leão, whose shot across goal was parried into the path of Tijjani Reijnders. The Dutchman roofed his finish past a mess of defenders.

The second half was a different story. Inter’s superior quality and depth of options off the bench were brought to bear as they opened a siege on Milan’s goal, hitting the woodwork three times as well as having a goal correctly disallowed – something that had already happened twice in the first half.

Right up to the 93rd minute, it appeared as though this was going to be Milan’s evening. They had ridden their luck but also defended assiduously. Walker was more solid than spectacular, but that felt a welcome enough change from the Emerson Royal rollercoaster that has preceded him. Tomori was everywhere, keeping track even with the electric Marcus Thuram. His six tackles were the most of anyone on the pitch.

A man of the match performance and easily his best of the season so far. Did Walker play some part? The latter spoke at his unveiling about needing, and wanting, to learn Italian, but here at least he was able to communicate easily with a new teammate.

As tempting as it is to get swept up in a narrative, more evidence is needed before we draw conclusions about their effectiveness together. This was a particular evening: a Milan derby that did not quite feel like one at the start. Police banned Ultras from putting on their usual choreographies amid an ongoing investigation into the alleged criminal ties of some members of organised supporter groups in the city.

Perhaps that absence contributed to the stodgier first half, that partially subdued energy of the stands reflected on the pitch. Or maybe those things were unrelated. Certainly, by the end it had become a full-blooded affair, Inter throwing themselves at Milan with ever-greater desperation, their manager, Simone Inzaghi, kicking holes in an advertising hoarding after seeing one too many shots come back off the post.

Inter felt aggrieved not to have been given a penalty when Hernández and Pavlovic combined to dispossess Thuram, the former getting the ball but his teammate appearing to catch the Inter forward’s ankle. But they would find their equaliser in injury time, the substitute Nicola Zalewski – a new signing of their own – chesting down a cross for Stefan de Vrij to finish.

It was a draw that suited nobody, Milan losing ground in the race for fourth while Inter dropped two points in the title race – though another last-gasp equaliser for Roma against Napoli later that evening preserved the status quo at the top. Inzaghi’s team can pull level with Antonio Conte’s if they beat Fiorentina on Thursday, in the resumption of a match suspended after the collapse of Edoardo Bove in December.

Atalanta 1-1 Torino, Bologna 2-0 Como, Fiorentina 2-1 Genoa, Juventus 4-1 Empoli, Milan 1-1 Internazionale, Monza 0-1 Verona, Parma 1-3 Lecce, Roma 1-1 Napoli, Udinese 3-2 Venezia

Monday Cagliari v Lazio (7.45pm GMT)

Milan are further adrift of their objectives, eighth in the table and potentially seven points off the Champions League spots if Lazio win their game against Cagliari on Monday night. They are moving aggressively in these final days of the window, having also added Santiago Giménez for €35m from Feyenoord and continuing to work on a loan deal for João Félix.

Conceição has had mixed results since opening his tenure by beating Juventus and Inter in the Supercoppa. A win and a draw in two derbies so far are more than most fans would have hoped for, but the midweek defeat to Dinamo Zagreb – which cost Milan automatic progress to the last 16 of the Champions League – felt like confirmation of the warning signs we had seen in their come-from-behind win over Parma the previous weekend.

Milan’s owners hope this string of high-profile signings to close out the transfer window can set their team on a more consistent track. At least one new arrival believes that they will. “An honour to make my Milan debut today,” wrote Walker in a social media post. “Frustrating not to take all 3 points, but I’m confident we’ve got plenty more to come.”