“Asking why Bobby doesn’t score more goals is like asking why the conductor doesn’t play the violin,” novelist John Green eloquently mused on Twitter following Roberto Firmino’s third goalless outing of the season, to much aplomb from fellow Liverpool fans.

It’s certainly true that Firmino’s unconventional qualities as a central striker have made him an instrumental idiosyncrasy of Jurgen Klopp’s system, and it’s certainly true that his primary function isn’t to ripple the net himself, but to find ways of allowing Mohamed Salah and Sadio Mane to do it instead with lethal regularity.

As one Liverpool analyst recently put it to Melissa Ready; “He is the system. No-one operates between the lines like him, no-one recovers the ball as well for our transitions, no-one understands and manipulates space as well and his first thought is always what can he do to benefit a team-mate or serve the system.”

But at what point does the accusation of football naivety and lazy analysis aimed at those who criticise the Anfield star become in fact naïve and lazy in itself? And at what point does the notion of Firmino doing the work that’s difficult to see in fact become a veil that blinds us from the reality of an attacking player who’s simply struggling to score goals and arguably slowing down?

Firmino has been a fundamental pillar of Klopp’s Liverpool evolution which has climaxed with European and domestic glory, but after a goal-shy 2019/20 season and an equally profligate start to the current campaign, question marks are legitimate and inevitable upon turning 29 - an age when many forwards enter their decline.

Because while Firmino’s influence on Liverpool’s attack is by nature difficult to define in purely statistical terms, some of the numbers do make for alarming reading. Chief among those is the fact Firmino produced his worst-ever scoring return in the Premier League last season, which saw his goal involvements per game average drop under 0.5 for the first time in his Liverpool career.

Roberto Firmino celebrates with Andrew Robertson

Most concerningly, he missed 20 big chances - the third-most of anyone in the Premier League - and while the analogy of a conductor fiddling a violin once again comes into play, the ultimate question is where exactly the line is drawn.

Is it acceptable for Firmino to notch single figures in the Premier League for two consecutive campaigns? Is it acceptable for him to go the entire 2020/21 season without scoring? This is, after all, a centre-forward for arguably the top club in European football, and this is, after all, a player Klopp has previously described positionally as “a nine and a half”.

Which, in many ways, encapsulates the troubling trend - Firmino is acting less and less like a centre-forward, almost to the point where Liverpool don’t have one at all. Instead of offering Liverpool another route to goal by making daring runs in front of or behind defenders in the box, he’s peeling back and leaving spaces vacant - as if to say others should be occupying them instead.

Roberto Firmino looks disappointed

That may not seem such a prevalent issue when Mane and Salah are competing with each other for the Golden Boot, but the brilliance of others can’t always be justification for limited direct involvement, and there’s surely a point when ghosting around the box in expectation for others to take the lead essentially becomes shirking responsibility.

Of course, the argument is that Firmino plays a crucial hand in pushing those around him to lofty heights, and some of the statistics do reflect that. Last season he averaged the most progressive runs per game of his Premier League stint, as well as his highest total for second assists across the season, with five in the top flight.

But other numbers juxtapose the above. Far from being crucial to recovering the ball for Liverpool’s transitions as the aforementioned analyst quipped, last season actually marked Firmino’s lowest per game returns for interceptionsoffensive duels won and recoveries in the opposition half, as well as his second lowest return for tackles.

Roberto Firmino challenges for the ball

It also marked his highest rate for unsuccessful touches per game and second lowest rate for key passes per game, and when all of these comparatively modest returns are put together, they’re made more troubling by the fact they came during what was Liverpool’s most dominant Premier League season of Klopp’s tenure - one that saw them win the title by 17 points and score 85 goals. In fact, the last two top flight campaigns have resulted in Firmino participating in his lowest percentage of Liverpool’s overall goals, 20% on each occasion.

“Firmino’s influence is most obvious in his absence,” JJ Bull scribed in The Telegraph back in 2019, and theoretically speaking, that still remains the case. Liverpool don’t have anyone else in the squad that offers what Firmino does, both in terms of his selflessness and his skillset. Liverpool’s win rate was 10% less across all competitions when the Brazilian didn’t start last season, and in two of the four Premier League games he was benched for, Liverpool didn’t take the lead until after he’d been introduced as a substitute.

That is of course very telling, but Firmino being an instrumental component of Klopp's system and lacking the form he showed a few years ago don't need to be mutually exclusive concepts, and the ultimate question is why Liverpool can’t find another striker that can offer something similar to what Firmino does, while providing more direct threat to goal.

Liverpool's Mohamed Salah, Roberto Firmino and Sadio Mane celebrate

Surely it can’t be the case that, throughout the entirety of world football, there is no elite forward who can both pull centre-backs out of position by dropping into midfield and act like a striker when he’s around the box. Surely Firmino wasn’t made in a laboratory, specifically to operate as Klopp’s false nine and bring the best out of Salah and Mane.

Liverpool need to find the answer to that question over the next few years, because at 29 Firmino isn’t getting any younger and the last 18 months of football have certainly hinted at the start of a decline. Those surging charges on the counter-attack are becoming less and less frequent, just as the confidence oozed through those trademark no-look finishes seems to have started to drain. and Firmino has now scored just six goals in his last 35 Premier League games, compared to 51 in his first 143 - that’s a percentage decrease of almost exactly half.

For now, the idea that Firmino’s brilliance is impossible to quantify continues to shield him from hefty criticism. But ultimately, even the most unconventional strikers are judged on how many they score and how many they create; while Firmino’s numbers in that respect have never been world-class, it does feel that we are teetering on a tipping point.

And when that’s combined with lesser per match statistics across the board, one has to wonder whether the problem isn’t in fact Firmino’s influence being misinterpreted, but rather the difficulties of interpreting him covering up an inevitable recession of abilities. As instrumental a player Firmino has been and continues to be for Klopp, Liverpool might, quite simply, have already seen the best of him.