How do you stop Leicester City? Even now, eight months into the season, it remains as much of a tantalising puzzle as a question. We have become fluent in their star names’ tricks and traits, while the Foxes’ distinct viciousness on the counterattack is a staple of Match of the Day highlight reels. Yet Claudio Ranieri’s side continue to be a footballing Enigma machine, refusing to yield all their secrets. Staggeringly, Leicester have lost only three times in the league this season – and only once, a 5-2 home loss to Arsenal in September, have they been properly filleted.

So how do you stop them? That was the question that Dan Altman – a Harvard-trained economist whose company North Yard Analytics works with a number of Premier League and Champions League clubs – set about answering at the MIT Sloan Sports Analytics Conference on Saturday. His starting point, he told his packed audience, was this fascinating nugget: “The more Leicester pass, the less Leicester score.”

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Altman knew this because he had analysed every single Leicester attack starting from within their own half this season. This involved examining the total length of passes in each move as well as whether that possession led to a shot and the quality of chance it produced. (Yes, that is a lot of number crunching). Crucially, it allowed him to work out how direct the Foxes’ attack was compared to other teams – and how the speed of their attacks affected their chance creation.

What Altman found was fascinating. First, Ranieri’s men created far better chances when they went for the jugular immediately. So if, say, they received the ball 80 yards from goal, their expected goals per possession was highest when the ball was passed between 80 and 120 yards before a shot. In other words, when they played direct football. However, when they played in a more measured style, similar to Arsenal or Manchester City, their chance of scoring was far lower than other teams around them in the league.

The data showed something else. Danny Drinkwater and N’Golo Kanté are often primarily regarded as supreme worker bees, protecting Leicester’s back four and growling away in midfield. Not without reason, given Kanté leads the league in interceptions and tackles. Yet, as Altman pointed out, for the first 16 games of this Premier League season the highest proportion of Leicester’s most dangerous attacks started with these two central midfielders – with long balls from their goalkeeper Kasper Schmeichel also prominent in the data.

So how might this help teams stop Leicester? Or at least slow them down? As Altman argued, given that Ranieri’s side need to be direct, teams should force them to the flanks more often because usually they will have to come back towards the centre to create better chances, which will blunt the speed of their attacks. They also need to press Drinkwater and Kanté with greater frequency.

Indeed, as Altman explained, this has started to happen. When he compared Leicester’s first 16 matches this season to their next 12, he found that because Drinkwater and Kanté were being harried more often the attacks they started were less effective. More of Leicester’s play was beginning and going through the flanks – and particularly the full-back Christian Fuchs.

The effect on Leicester’s attack is notable. Over games 17 to 28 in the Premier League, their shots from possessions starting in their own half tumbled by 50%. Meanwhile, the expected goals from these possessions – a measure of how good their chances were – fell by 25%. To Altman, this meant that pressing the midfielders had been successful, although it also had a cost: Leicester’s shots from counterattacks fell but the quality of those shots rose. The reason was simple: attacks that did get through the press had fewer defenders to beat further up the field.

Altman stressed that his presentation was not a comprehensive master plan to stopping Leicester but a small snapshot showing how deeply mining data, along with using more traditional methods such as video analysis, could help teams potentially develop an edge.

As he also points out, the data suggests Leicester have other potential weaknesses that might yet be exploited, such as Schmeichel. “He is often pivotal in starting attacks, so opposing forwards should probably hassle him more when he has the ball,” Altman says. “And though he’s a good shot-stopper, he’s below average at cleaning up the play after shots that don’t result in goals, so opposing players should always be ready to charge in for a rebound.”

Still, these potential weaknesses are not yet greatly affecting Leicester’s results. For months the doubters and sceptics have expected them to slip back to their rightful place. Yet winter has gambolled into spring and the Foxes have become favourites for the Premier League – aided, Altman says, by a dose of luck.

That is certainly the case, but if Leicester can rebuff Spurs and the rest, few would begrudge them the title. True, they have also benefited from this most gloriously bonkers season in memory, with Chelsea, Manchester City and Manchester United all wildly underperforming and Arsenal imploding when coming up on the rails. However, it took balls and bravado for Ranieri’s side to seize the day – as well as superb recruitment, canny management and Jamie Vardy and Riyad Mahrez producing a season for the ages.

For decades Leicester have been the most blue collar of teams. Now, wondrously, they appear smarter and sharper than the pack.