Monaco knows it’s capable of scoring the goals required to overcome Manchester City and reach the Champions League quarter-finals. Leonardo Jardim’s team has banged in 123 already this season, at an astonishing rate of 2.67 per game. The Ligue 1 club raised that average a little further last month at the Etihad – sticking three past Willy Caballero. In theory, Monaco only needs two more to progress.

In practice, things are unlikely to be quite so straightforward. Two goals will suffice on Wednesday only if Monaco can keep a clean sheet, something it has done just twice in 11 European games. Shutting out a City side that netted five in the first leg is probably an unrealistic target.

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What will be imperative for Monaco is to avoid conceding more than twice. A 3-1 or even a 4-2 victory for the Ligue 1 leader would still be good enough to progress – thanks to the away goals rule. Even those outcomes, though, would require significant improvement at the back.

The task is rendered more complicated by the fact that Monaco will not be at full-strength. Kamil Glik is suspended at centre-back, depriving Monaco of a crucial aerial presence. The Poland international has won more headers in this tournament than any team-mate besides the centre-forward Guido Carrillo. There is no other defender in the squad who can match his 6-foot-3 stature.

More than that, the sheer unfamiliarity of playing without Glik may unsettle Monaco. He has been a fixture of Jardim’s team ever since joining from Torino in the summer, prized by the manager for both his physicality and his leadership. Not even the starting goalkeeper, Danijel Subasic, has played as many minutes across all competitions.

And yet, the truth is that Glik struggled at the Etihad. He failed to track Leroy Sane’s run for City’s first goal and lost John Stones at a corner for the fourth. Although he was not primarily to blame for their second, he could have been quicker in getting across to Sergio Aguero there, too.

Whilst Glik’s absence could hardly be characterised as a positive, it might be outweighed by the return of the player who typically plays alongside him. Jemerson missed the first leg due to a suspension of his own, but will be back for the second leg. He might be just the man Monaco needs.

That is an extraordinary thing to say of a player who less than three years ago was nothing more than a reserve at Atletico Mineiro in Brazil. He got an extended run of first-team games in 2014 only after starting centre-back Rever went down injured.

Nothing about Jemerson’s career has been obvious. Having grown up outside of any football academy system, he did not have a fixed position – playing everywhere from centre-forward to goalkeeper – before he joined Confianca – a modest regional side – at the age of 16. He almost quit football altogether one year later, when he was not offered a professional contract as quickly as others from his cohort.

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Rogerio Micale, who coached Atletico Mineiro’s Under-20 team before moving on to oversee the Brazilian national side in that age group, told L’Equipe this week that he used to worry about Jemerson’s timidity – claiming that the player would always stare down at his socks when spoken to.

“But I realised he was talking with his feet, like Garrincha,” continued Micale. “For me, Jemerson has nothing to envy of Thiago Silva, Marquinhos, Miranda or David Luiz. He will become one of the best defenders in the world.”

Certainly, Jemerson is not at that level yet. But he is a very different defender to Glik, one with the pace and athleticism to run with City’s quicker forwards. He is far more aggressive in the challenge than his partner – a double-edged sword, to be certain, but often an effective one.

Jemerson has won an average of 3.2 tackles per game in the Champions League this season, compared to Glik’s 0.5. The numbers in Ligue 1 follow a similar pattern (2.4 to 0.7), and the Brazilian makes more interceptions as well.

Whether he can be similarly effective without Glik alongside him might be the single most important question for Monaco heading into Wednesday night. Andrea Raggi is a willing player but a limited one, and has played more often at full-back this season than in the middle of defence. He struggled filling in for Jemerson at the Etihad and may be no better suited to replacing the Pole.

For Monaco to have any hopes of success, though, Jardim’s side will also require improved attentiveness from both full-backs. Benjamin Mendy and Djibril Sidibe both joined Monaco together with Glik last summer.

Their dynamism and crossing ability have been key assets in this barnstorming season, but both were exposed at times in the first leg. It was Mendy’s lazy marking of Aguero at a corner in the 71st minute that allowed the Argentinian space to volley home a finish that leveled the scores at 3-3, and launched City’s game-winning flurry.

At the Stade Louis II, no such generosity can be afforded.

Les Rouges et Blanc have the firepower to beat Manchester City. But only if they don’t get gunned down themselves first.