Romelu Lukaku’s best goal yet for Internazionale. Cristiano Ronaldo bagging a 95th-minute winner to put Juventus back on top of the table. Six players sent off in an evening, and Carlo Ancelotti seeing red, too, after his Napoli team blew their second lead of the night against Atalanta. Serie A’s midweek round was certainly eventful.

We will get to all the stories mentioned above, but this also feels like a moment when we need to talk about Chris Smalling. He scored his first Serie A goal on Wednesday, the second of four in Roma’s romp past Udinese. The strike itself was nothing special – not even the best of the night by a centre-back playing for a club from Italy’s capital – but it was a moment to cherish for a player who has relaunched his career superbly in Italy over the past couple of months.

Smalling’s arrival in late August felt like an afterthought. Roma had been working throughout the transfer window to reinforce a defence that conceded 48 goals last season, and which lost its one reliable performer when Napoli triggered Kostas Manolas’s release clause.

Gianluca Mancini was signed from Atalanta – a richly-talented 23-year-old who had won his first senior Italy caps earlier in the year – but attempts to bring in an experienced partner to play alongside him were less successful. Roma landed on Smalling only after having bids for Toby Alderweireld and Dejan Lovren turned down. Fiorentina’s German Pezzella and Juventus’s Daniele Rugani were also considered, but in both cases the asking price was too high.

Perhaps it was all for the best. Smalling came cheap – the fee has been reported at €3m for a one-year loan – and has quickly become a fixture of Roma’s starting XI. More than that, he is playing well. Through six Serie A appearances, no opponent has dribbled past him, and he has succeeded with 100% of his attempted tackles.

He is well-suited to the style of football preferred by Paulo Fonseca. The Roma manager, hired from Shakhtar Donetsk in the summer, prefers a high defensive line, making pace an essential trait for his centre-backs. Smalling told Roma’s club website this month that he has enjoyed being placed in individual duels.

“In England quite often you have to deal with just one striker, so you’ve got your other central defender covering you – whereas often here you can be left two-on-two a lot of the time,” he said. “There’s a lot more runs in behind being made too … I’m enjoying it – because I quite like a tussle and a sprint against the striker. It definitely suits my game.”

Fonseca’s Roma are a team in evolution, still adapting to the coach’s ideas. Early in the season, the commitment to pressing opponents inside their own half bordered on the reckless, leading to chaotic end-to-end matches against Genoa and Sassuolo. More recently, there has been greater balance, though that is aided too by Smalling’s recovery speed – a sharp contrast with the week-one starter, Juan Jesus.

That the Englishman is taking on his coaches’ instructions is evident in other areas, too. When Edin Dzeko scored Roma’s opener against Milan at the weekend, it was with the assistance of a well-choreographed crossing run from Smalling, to take out his marker at a corner.

Conversely, his most frustrating moment to date only won him more sympathy from Roma’s supporters. Smalling was adjudged to have given away a penalty in the 90th minute of his team’s Europa League game against Borussia Mönchengladbach, allowing the Germans to equalise. In reality, the ball hit him in the face. Social media was awash with surrealist memes.

Even putting his goal to one side, Smalling played well again on Wednesday. His centre-back partner Federico Fazio was harshly sent off after half an hour following a coming-together with Stefano Okaka, but Roma, already a goal up by that stage, rarely looked in danger of conceding after they were reduced to 10 men.

Mancini, who started in midfield, dropped back into defence in what became a 4-4-1, but the Giallorossi continued to dictate the play. Smalling made the score 2-0 when he pounced on Kevin Lasagna’s uncertain touch at a corner, jabbing the ball home at the back post. Justin Kluivert and Aleksandar Kolarov completed the rout.

Asked afterwards whether his loan move to Roma could become permanent, Smalling deferred, saying that: “Anything could happen.” The club, at least, are keen, with the sporting director, Gianluca Petrachi, suggesting that he would open discussions with United if the player wanted to stay.

Victory moved Roma up to fourth, an impressive position when set against their lengthy injury list. Bryan Cristante, Lorenzo Pellegrini, Amadou Diawara, Henrikh Mkhitaryan, Davide Zappacosta and Nikola Kalinic are all presently sidelined. Edin Dzeko has been playing in a protective face mask after fracturing his cheekbone.

Despite it all, they are now ahead of Napoli – whose draw against Atalanta arrived in controversial circumstances. The Partenopei were leading 2-1 in the 85th minute when Simon Kjaer rugby-tackled Fernando Llorente in the penalty area. Play continued, and Atalanta scored at the far end.

It was precisely the sort of refereeing error that VAR was designed to correct. Yet the officials in the replay booth never recommended that Piero Giacomelli conduct a pitch-side review. Some commentators have since suggested that Llorente initiated the contact with Kjaer, making it impossible to call this a “clear and obvious” penalty decision. This column respectfully disagrees.

Asked about his red card, Ancelotti claimed the referee had asked him to help restore order among furious players. “I said: ‘Don’t you think there’s even a chance it could have been a penalty?’ In response, he threw me out. I feel as though my professionalism has been attacked.”

Further contentious decisions would follow in Turin, where Juventus’s winning goal came from a Ronaldo penalty which he earned for himself in second-half injury time. Antonio Sanabria’s challenge was clumsy and perhaps made enough contact with the forward’s shin to justify a spot-kick. But Ronaldo’s delayed reaction and exaggerated fall, deliberately kicking out his back leg, looked more ridiculous with each repeat viewing.

The second booking collected by Genoa’s Francesco Cassata earlier in the match, furthermore, was hard to justify. It all added up to a bullet dodged by Juventus – wearing a bizarre fourth-kit with fluorescent green sponsor’s logo – who did not play at all well.

Nor, truthfully, did Inter in their victory over Brescia on Tuesday. The goals of Lukaku and Lautaro Martínez, who opened the scoring with a heavily deflected shot, are covering a lot of ills for Antonio Conte’s team.

Yet the Belgian’s run to celebrate with his manager, after bending his shot into the far corner from 20 yards, felt like the key visual from this game. Conte, just like Fonseca with Smalling at Roma, is getting the most out of a player who Manchester United were only too happy to discard.