One presumes a plastic ruler is in the post. After listening to his opposite number at Roma, Dino Viola, complain about the legitimacy of the decisive goal in a 3-1 defeat to Juventus at the Olimpico in the spring of 1983, Bianconeri president Giampiero Boniperti went out and bought him one so he could measure how far Michel Platini was offside when he crossed for Sergio Brio to score.
Roma would win the Scudetto that season but two years earlier believed they had been denied it when Maurizio Turone's winning goal in Turin was contentiously ruled out. Cesare Prandelli, asleep at the far post, appeared to be playing him onside but the linesman, Giuliano Sancini, a gift-shop salesman from Bologna, thought otherwise and raised his flag. Had it stood, Roma would probably have gone on to claim their first title in almost four decades.
Those incidents are still spoken about to this day, and Sunday's 3-2 Juve win will be for a long time, too.
"They will talk about it forever and ever in the office, the factory, at school, on the tram, on Twitter, TV, and in the papers," Maurizio Crosetti wrote in La Repubblica. Rather than a football ground, La Stampa's Massimiliano Nerozzi felt the Juventus Stadium had taken on the atmosphere of a Wild West "saloon."
How curious it should turn out that way after his story about Arturo Vidal not being included in the starting lineup on the basis that he had got involved in a fight in Turin city centre after going out clubbing on Thursday night. In hindsight, he couldn't have prepared himself better.
Make no mistake -- something that couldn't be said of referee Gianluca Rocchi -- this was a bar-room brawl, and it ended with Juventus coach Massimiliano Allegri separating his striker Alvaro Morata and Roma defender Kostas Manolas as though he were Mills Lane stepping between a pair of heavyweight boxers at the MGM Grand in Las Vegas. They both saw red, and weren't the only ones. Roma coach Rudi Garcia, who had insisted his players wouldn't be bringing their "dancing shoes" to Turin, had already received his marching orders in the first half.
His pretending to play the violin -- or bad conduct -- at the sob story Juventus players appeared to be telling Rocchi following his decision to give a penalty after initially awarding only a free kick called to mind Jose Mourinho's famous handcuff gesture when Inter Milan went down to nine men against Sampdoria in 2010. A set piece effort from the returning Andrea Pirlo had struck Maicon above the elbow, yet upon leaping to block it he moved forward and the contact seemed to take place inches outside the box.
"It was our fault we lost too," Garcia would later say in reaction, "but it's a shame the penalty area here is 19 yards." Again, his comments echoed ones Mourinho had made after a similar decision had been made in Juventus' favour against Genoa in 2010, when the Portuguese said: "I don't stick my head in the sand, I know there is only one team that has a penalty area 25 metres long.''
Countering the latest remarks, Juventus general manager Beppe Marotta reminded him that Roma had been granted a very similar penalty in Turin four years ago after a handball was given against Simone Pepe on the edge of the area when facing a Francesco Totti free kick.
It's swings and roundabouts, as they say. Of course, all this wouldn't have happened had Totti himself not fouled Pirlo with an unnecessary challenge moments earlier. But tensions had already risen. Claudio Marchisio had previously gone down claiming a penalty following a coming together with Jose Holebas. Rocchi let it go amid protests. How much they perhaps conditioned him into giving Juventus the benefit of the doubt after the Maicon incident we'll never know. By then he'd lost the game. It was a "Rocchi horror show."
Carlos Tevez put Juventus in front from 12 yards, scoring his first goal against Roma. Five minutes later, however, the away side were back level. Rocchi was again pointing to the spot after Stephan Lichtsteiner rugby-tackled Totti to the floor. Even this was called into question in the papers on Monday. Had he fouled Lichtsteiner prior to being sacked? For Gazzetta he had. Rocchi missed that, but the Roma captain didn't miss from the spot and got the Giallorossi back on level terms. By doing so he brought an end to his friend Gigi Buffon's run of not conceding a goal in Serie A after 833 minutes.
Heated like a Copa Libertadores game, all the blood, thunder, machismo of it -- in addition to Rocchi distributing cards as though they were confetti -- led Sky Italia's pundits Luca Marchegiani and Massimo Mauro to declare it an ugly spectacle. It was supposed to be an advert for the Italian game, with Bayern Munich boss Pep Guardiola among the attendees. "For once European football had turned its spotlight on us," Luca Calamai wrote in La Gazzetta dello Sport. "Instead we ended up prisoners of our usual vices." Not everyone agreed, though.
"It's been a long time since we saw intensity of that nature in the Italian league," Il Corriere della Sera's Mario Sconcerti insisted. There were moments of quality too. The speed and synchronicity with which Gervinho and Juan Manuel Iturbe combined to give Roma the lead was such that it led Juventus centre-back Martin Caceres to pull a muscle.
Iturbe, the most expensive summer signing in Italy, had seemed destined for a move to Juventus this summer. A plane ticket from Frankfurt to Turin had been booked in his name, only for Roma to swoop while their rivals absorbed the shock of Antonio Conte's resignation.
The ailing Caceres, still on the pitch, was then left in Gervinho's wake again. He should have made it 3-1. Instead Roma went in at the interval pegged back and with the score 2-2. Even with only a minute of injury time allocated at the end of the first half -- an absurd amount considering the many incidents of the opening 45 -- Rocchi pointed to the spot again as Miralem Pjanic slid in to stop an incursion into the box from Paul Pogba. Again the debate centred on whether it was inside or outside. "Only God could have seen it," Sconcerti wrote.
How Rocchi did is a mystery. For Romanisti inevitably it was conspiracy, even if these things do happen. Recall for instance how Gervinho won a penalty against Inter last season following a challenge from outside the area by Alvaro Pereira. "Can I say something about the refereeing?" Garcia asked on Sky Italia after Sunday's game. "We need to help the referees." He called for technology to be introduced for penalty-box incidents.
Even when the replays were stopped and started over and over again, however, consensus was hard to reach on the Maicon and Pjanic decisions. The margins were so fine, the area neither black nor white but grey.
Yet again Tevez made no mistake from the dischetto (little disc), as it's known in Italy -- that's now eight goals in seven games for the "Apache" who could easily be forgiven for thinking he was involved in a bad-tempered Super Clasico between former club Boca Juniors and River Plate.
In the latter stages of the first half and into the second, Roma shaded it. Seydou Keita was magnificent in midfield, while Gervinho and Iturbe continued to menace. Regrets -- Pjanic must have a few. After his needless lunge on Pogba -- which he shouldn't have made, as Manolas had him covered -- Gervinho presented him with the chance to make it 3-2 to the visitors only for the playmaker to skew his shot agonisingly wide. If only he could score "easy goals" as well as those highlight-reel lobs and Maradona-like runs, was the refrain.
Should this have been a boxing match, the middle rounds would without doubt have gone to Roma. However, Juventus finished as they started: strongly. Morata came on for the ineffective Fernando Llorente and, after nodding his first goal in against Atalanta last week, headed against the crossbar this time. Then, four minutes from the end, came the stunning coup de grace. Leonardo Bonucci, a scorer in their last meeting in Turin, got the winner with a fine strike from outside the area. But its validity was also much discussed.
Positioned in front of Roma's stand-in goalkeeper Lukasz Skorupski, it was asked whether Vidal was interfering with play. Did he obstruct the Pole's line of sight? Rocchi thought not. Perhaps he had Klaas-Jan Huntelaar's goal against Maribor in the Champions League in mind when Julian Draxler ran across and jumped over his shot's path. A still image shows Skorupski's view to be relatively clear, but in real time, how long was it unimpeded?
Crosetti's assessment that this game was "manna from heaven for the moviolisti" -- Italy's replay analysts/anoraks/obsessives -- was spot on, as was his colleague Gianni Mura's assertion that Rocchi and his errors of judgement "took transparency away from Juventus' victory." They have instead regenerated a climate of scepticism and distrust. "We came here to win but unfortunately what happened conditioned everything," Totti said. "As long as there's Juve, we'll always come second. They should have a league of their own. We've reinforced but, when you meet them, what happens happens. It's been years now that this is the tendency."
Memories of the Turone goal, Boniperti's ruler and Calciopoli make it hard for Romanisti to believe referees make mistakes in good faith, even if the old network of influence espoused by Juventus' former general manager Luciano Moggi was dismantled and he was banished from the game after the scandal in 2006. Juventus paid dearly for it, suffering relegation to Serie B, and finished seventh in back-to-back seasons before Conte led them back to the top for three straight years.
No one would dispute they deserved those titles, nor their status as the best team in Italy. Unfortunately their cross to bear is to live with this residual suspicion.
The Rome-based papers did little to discourage that on Monday. "Everybody stop, this is a robbery," Il Tempo proclaimed. "Campionato Falsato," Il Corriere dello Sport announced. The league has been falsified.
Roma have to channel the injustice they are experiencing now. Confronted on Sunday by a choreography from the Juventus fans showing the number 102 -- last season's record point total -- the counterintuitive sensation is that Roma have actually closed the gap even if they suffered their first defeat of the campaign and are now three points behind the champions.
Having been beaten 14-1 across their previous four visits to the Juventus Stadium, to lose only by a goal in these circumstances -- notably the refereeing and absences of Morgan De Sanctis, Davide Astori, Leandro Castan, Daniele De Rossi and Kevin Strootman -- and fire two past a goalkeeper who hadn't conceded in nine league games should be of some consolation. And let's not forget there are still another 96 points to play for.
As for Juventus, if you can abstract their performance -- and particularly those of Bonucci, Marchisio and Tevez -- from Rocchi's, this team's courage, mental strength, hunger and sheer bloody-mindedness to come back and win must be begrudgingly admired. Still perfect in Serie A, Sunday's win was their 22nd in a row at home in the league, breaking the record established by the Grande Torino in 1947-48.
The mood could have quite easily altered around Allegri had he lost this after Wednesday's defeat to Atletico Madrid. Instead, he was smiling even after another heated exchange with Arrigo Sacchi on Mediaset. "I'd like to thank the lads again because I can now have a pleasant international break," he quipped. Romanisti, meanwhile, will need a fortnight to get over it. Then they must go again.