Eddie Howe needs Alexander Isak in Newcastle's starting side

As he ponders how best to kickstart Newcastle United’s stuttering season ahead of Saturday’s daunting trip to Manchester City, Eddie Howe needs to stop wavering over Alexander Isak. After six months of easing the 23-year-old in – a spell that, admittedly, has been affected by injuries – it is time to see what Newcastle’s standout summer addition is capable of.

Is Isak an orthodox number nine, whose best performances will always generally come when he is played through the middle? Is he a wide-attacker, ideally suited to Newcastle’s current 4-3-3 formation? Is he best playing as a ‘number ten’, as he did when he came off the bench for Sunday’s Carabao Cup final at Wembley, with his pace and movement providing the ideal foil for another forward playing ahead of him? Or is his optimal role actually as an impact substitute, making a difference off the bench?

The truth is, we simply do not know, because since signing from Real Sociedad in the summer, his opportunities have been extremely limited. He has started just five Premier League matches, with another two league appearances coming as a substitute off the bench, and has made one more start and four more substitute appearances in the cup competitions. He has played a total of 904 minutes in a Newcastle shirt, scoring three goals and claiming one assist, and posting a shots-per-goal ratio of 1.4. There have been plenty of signs of promise, but nothing to conclusively prove whether he is the answer to the Magpies’ current goalscoring problems or not. It is time to find out.

Newcastle’s effectiveness in front of goal has dipped markedly since the post-World Cup return of domestic competition. Prior to the World Cup break, the Magpies had the sixth-best performance stats when it came to outperforming their expected goals (xG) tally. Across 15 matches, they scored 29 goals when the data analysis suggested they should have scored 24.99.

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Since the post-World Cup resumption, no Premier League side has delivered worse results than Newcastle when it comes to failing to match their expected goals. In eight matches, Newcastle have scored six goals, despite their xG total suggesting they should have scored 13.1.

That is a stark difference, and while there are a host of contributory factors – Miguel Almiron’s effectiveness has dipped markedly since his autumn purple patch, Kieran Trippier’s set-piece deliveries have been patchy at best, defenders have spurned a number of decent headed opportunities from within the opposition’s 18-yard box – Callum Wilson’s lack of form is undoubtedly a key explanation for Newcastle’s struggles in front of goal.

Whether because of the ongoing effects of the injury that he carried into the World Cup finals and that might well not have been comprehensively addressed since, or because of the impact of the illness that affected him when he returned from Qatar, Wilson has simply not been right since the turn of the year. After his failure to find the net on Sunday, he has now scored just one goal in his last 15 matches for club and country.

His sharpness has been missing, as was highlighted by his failure to get a shot away when he broke into the 18-yard box during the second half of last month’s draw with West Ham, and while his commitment and work rate cannot be questioned, he has struggled to link play in recent weeks or pull opposition defenders out of position to create space for others to exploit.

Callum Wilson can't get past Lisandro Martinez during Newcastle's defeat in the Carabao Cup final (Image: PA)

His weekend performance at Wembley was indicative of his recent struggles – there was plenty of huffing and puffing, and closing down of the Manchester United defence, but at no stage did he look like seriously threatening David de Gea.

There were calls to make attacking changes to get Isak into the team ahead of Sunday’s outing at Wembley, but having put so much faith in the line-up that started the game throughout the course of the season so far, Howe was always going to stick with the tried-and-tested for his first major final. In the Magpies manager’s mind, Wilson had done more than enough to earn his faith and trust, and he wasn’t going to rip up his preferred tactical template just to try to get his number nine and Isak into the same team.

Given the magnitude of the game, that was probably fair enough, but it didn’t work on Sunday, it hasn’t really worked for the last couple of months, and the time has finally arrived to accept that a change is needed.

That could simply mean replacing Wilson with Isak at the Etihad Stadium on Saturday, with Manchester City’s aggressive high press and recent tendency to play with three at the back potentially leaving spaces for the Swede to exploit.

However, on admittedly limited evidence, Isak has tended to look more at home with a freer attacking role, which might tempt Howe to adopt something like the formation that Newcastle adopted for the second half of Sunday’s final, with Isak playing off Wilson.

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That would require a fairly radical tactical tweak, and would mean having to leave one, or possibly two, of Almiron, Allan Saint-Maximin and Joelinton out of the starting side. There is also Anthony Gordon to factor into the equation now he is no longer cup-tied.

Howe has made plenty of bold calls during his year-and-a-half as Newcastle manager, but in terms of his tactics and starting selections, he has tended to be fairly conservative, With his side unquestionably misfiring, this feels like the time to shake things up.

As Sunday proved, Howe does not have the luxury of a particularly deep squad. He does, however, have a £63m striker on the bench, a situation that looks increasingly untenable as Newcastle continue to misfire in front of goal.