Since the glory days of the mid-1980s ebbed away and Everton slipped into post-Heysel doldrums that would twice take them to the brink of demotion from the Premier League, Goodison Park has become something of a striker's graveyard. Not since Gary Lineker's epic haul in the 1985-86 season that, combined with his exploits for England at the Mexico World Cup, helped usher him out the door destined for Barcelona, has an Everton forward reached the 20 League goal landmark... the one against which great strikers are measured and on which successful teams are founded

Only three forwards have come close in the Premier League era – Andrei Kanchelskis and Tony Cottee reached 16 and Yakubu, the most recent, scored 15 – but the club as a whole have struggled to find that one vital ingredient: a player who can not only fire 20 goals in a season but do so on a regular basis. Continuity up front has been as elusive for the Blues as silverware over the past couple of decades.

The arrival of Romelu Lukaku, first on a season-long loan and now on a permanent contract, promised to change that. Both times he has arrived at Goodison Park on a wave of excitement and anticipation – the New Drogba coming spearhead the Roberto Martinez revolution – but while he delivered 15 Premier League goals last term, this season has been harder going. Thanks to a pre-season disrupted by the World Cup and a frustrating toe injury, he has been showing patchy form and has just four goals in 11 appearances. Murmurings of criticism from some sections of the fanbase, restless for success and expecting great things from the new £28m signing, have started to grow louder, perhaps making that hefty price tag hanging around the Belgian's neck be feel a little bit heavier as time goes on.

Part of it is down to the scintillating way in which he introduced himself to the Everton faithful last year, starting with the excitement of his very arrival on deadline day with just minutes to spare as part of a triumverate of key acquisitions rounded out by Gareth Barry and James McCarthy. A debut goal at Upton Park – a headed winner in which he knocked himself out in a collision with a defender – was followed by a brace against Newcastle on his first appearance at Goodison and the then 21 year-old looked unstoppable.

His run of nine goals from 21 games came was stopped, though, by an ankle injury suffered in the debacle at Anfield at the end of January, but he returned to the side after a four-game absence to notch seven goals in 13 appearances in all competitions, galvinising the fans' affection for him and leaving Evertonians to rue the fact that he was sure to play his way to a big-money move to a Champions League team with his country at the World Cup in the summer.

His experience in Brazil would foreshadow what has been, by the standards he set in two season-long loan spells at West Bromwich Albion and Everton over the previous two seasons, a disappointing start to 2014-15. Isolated by poor service and hampered, perhaps, by his own lack of movement, Lukaku was withdrawn by national coach Marc Wilmots before an hour had elapsed in both of Belgium's opening matches in Group H. But, after being demoted to substitute for the Belgians' next two games, he came off the bench to score a typically rampaging winner to break the resistance of the United States in the round of 16. The erraticism of the young attacker in microcosm.

What followed was Everton not just breaking their previous incoming transfer record but obliterating it to land a player whom Roberto Martinez believes can develop into one of the best strikers of the Premier League era. With that massive price tag – though paid installments, the fee represented the equivalent of the club's profit for 2013-14 – comes an enormous weight of expectation, however, and it's possible, though neither he nor his manager would admit as much, that the 21 year-old is finding it a heavy burden at the moment.

It's hard to say definitively because the beginning of Lukaku's life as a full-time Everton player has not been ideal. Together with his compatriot, Kevin Mirallas, he had an extended break after the World Cup and his transfer to Goodison dragged on until the end of July, meaning he had little time with the squad in pre-season. Though he spent some time training at his old club Anderlecht to keep his fitness levels up, it was clear once the season proper got underway that he had a way to go before his match sharpness was back to acceptable levels.

That was compounded, of course, by an unspecified toe injury that appears to have dogged him all the way to the beginning of November, by which time his overall fitness appeared to be reaching desirable levels. Meaning that, perhaps, for the first time in 2014-15, Evertonians might be able to properly judge what they can expect from Lukaku over the rest of the season and beyond. The Toffees' last two matches stand wholly at odds with each other, though, keeping the waters muddied for the time being. Having put in what was unquestionably his most complete display in the home game against Lille – a game which Everton won in handsome fashion and Lukaku was denied what looked to be a legitimate goal by an offside flag – Romelu betrayed some of that early-season sloppiness at the Stadium of Light where his touch and hold-up play again let him down and he passed up a gilt-edged chance put his side ahead early in the second half of a disappointing 1-1 draw.

Martinez is adamant that his prize capture, a player for whom he said he would have paid four times more if needed, will take off now that he has recovered his fitness. It could be, however, that Lukaku needs the manager to find a few answers of his own before that becomes a reality. The return from injury of Ross Barkley was heralded as a potential key to the Belgian's form and a goal against Aston Villa set up by the former and finished by the latter appeared to emphasise the point. In being chopped and changed with Samuel Eto'o and Steven Naismith, though, Barkley has yet to find his own rhythm and there is a general lack of continuity in the attack that is hindering the Blues a little going forward in general.

Though Lukaku revelled in an unfamiliar wide role in those famous win over Arsenal and Manchester United back in April, where he terrorised the opposition defence by running at them from deep, he is at his best playing off the shoulder of the last defender – witness his goal against Crystal Palace – and and peeling off his marker in the box to meet crosses from out wide. Despite his 6' 4" frame, he is average in the air and has looked less effective as the target man charged with holding the ball up to bring others into play. It's an area of his game that Duncan Ferguson is working on at Finch Farm and which definitely showed signs of improvement against Lille, but it's finding the seams in defences to latch onto through-balls or charging away on the counter-attack where he seems to excel. With Everton employing such a patient, measured passing game at the moment, it doesn't feel as though the team is set up to play to those strengths.

Of course, while he isn't scoring at the rate to which we have become accustomed, Lukaku's contributions go beyond mere goals and Naismith has been the beneficiary. With opposition defenders focused on the big Belgian, the nimble Scot has plundered five goals in 11 starts, providing a valuable source of goals when they're not coming from his more expensive strike partner. £28m is obviously a lot to pay for a decoy but it's worth acknowledging that there is more to Lukaku than a reliance on goals.

It's also worth remembering that he is still only 21, not much older than Barkley who is, rightly, afforded plenty of latitude to continue his development and make his mistakes while learning his trade. In that respect Rom is something of a victim of his early success but it's up to him to prove now that he is worth every penny and more of that huge transfer fee. He has been accused of appearing to lack hunger on the field; whether that's because of the pressure of those great expectations or something deeper rooted remains to be seen but therein lies the key to the Lukaku question. It is no mystery what he's capable of; it's up to him to seize his moment.