By Editor Wayne Veysey

Theo Walcott and Alex Oxlade-Chamberlain joined Arsenal’s growing casualty list on a painful night for the club as they were eliminated from the League Cup by Sheffield Wednesday on Tuesday.

The key duo became the latest in a series of Gunners’ stars to break down with muscle injuries during matches and will be sidelined for key forthcoming fixtures.

Aaron Ramsey, Laurent Koscielny and Mathieu Flamini have also been forced off through injury in recent weeks in what is a damning indictment of Arsenal’s injury prevention methods.

So, who is to blame for the slew of soft tissue problems? Is it the fitness and medical staff? The players themselves? Or does responsibility rest upon the coaches and, ultimately, the manager Arsene Wenger?

Training drill: Shad Forsythe guides the Arsenal players through a session

Training drill: Shad Forsythe guides the Arsenal players through a session

The fitness coaches

They are responsible for overseeing the fitness and rehabilitation programmes of the first-team players. They guide the players through warm-ups and warm-downs in training and on match-days to get them in top condition to play.

Arsenal shook up their backroom staff when they appointed American Shad Forsythe as their new fitness guru in the wake of the 2014 World Cup following years of injury-ravaged campaigns.

Forsythe, who had spent a decade overseeing the fitness preparation of the Germany national team, was appointed as head of performance to share first-team duties with the Gunners’ long-standing fitness coach Tony Colbert.

Forsythe’s more modernistic injury prevention methods gradually bore fruit in his first season, as Arsenal finished the campaign strongly and the manager, used to having a decimated squad in the final months of a campaign, was able to select from virtually a full-strength squad. Arsenal felt the Forsythe effect.

It was a similar story in the early months of the new campaign, despite Jack Wilshere and Danny Welbeck being forced to undergo surgery.

So, why the sudden bout of hamstring injuries? Why have Oxlade-Chamberlain, Koscielny, Ramsey and Flamini all suffered hamstring injuries over the last month? Why did Walcott only last 13 minutes against Wednesday before being hauled off with a calf strain?

Have the warm-ups changed? Are the fitness staff being over-ruled by the coaching staff? Something has clearly gone badly wrong on the injury prevention front.

Injury expert: Colin Lewin heads Arsenal's physiotherapy department

Injury expert: Colin Lewin heads Arsenal’s physiotherapy department

The medical staff

As one of the world’s best-resourced clubs, Arsenal have invested substantial funds in their medical department, including the creation of what they claim is a “state-of-the-art medical centre” at their London Colney headquarters four years ago.

Yet, the role of the medical department, led by Colin Lewin, the head of medical services, is to treat and rehabilitate injured players. When it comes to preventing injuries in the first place and keeping players fit, fresh and in top condition, that is principally the domain of the fitness staff, in consultation with the coaches.

Arsenal’s medics are tainted by association. It is Lewin who is seen alongside the manager in the dugout and running on to the pitch to treat injured players on match days. In reality, he is dealing with problems partly created by others.

The players

Some players are willing to put their bodies on the line and play through the pain barrier. Hard-as-nails Olivier Giroud is a good example. Others only want to take to the field when they are feeling 100 per cent fit. Tomas Rosicky, for instance.

Yet most players are soldiers who respond to the instructions they are given, be it by fitness or medical specialists, or the coaching staff. If they do not do what they are told, they are putting their careers at risk.

It was noticeable against Sheffield Wednesday on Tuesday, as it became clear that Oxlade-Chamberlain would have to come off after just five minutes, that Walcott was not properly prepared.

He looked aggrieved when Wenger instructed him to cut short a warm-up that had barely begun, but obliged his manager by immediately taking to the field. He was not in the correct condition to play and both Walcott and the team have paid the price with the calf strain that will sideline him for at least the next three weeks.

Should an experienced player like Walcott, who knows his body better than anyone else, have been stronger and told his manager to wait a few minutes while he stretched his explosive leg muscles? Maybe. But the evidence suggests he was hung out to dry by Wenger.

Overall control: The buck ultimately rests with manager Arsene Wenger

Overall control: The buck ultimately stops with manager Arsene Wenger

The manager

Ultimately, responsibility rests with the manager. And no manager in the Premier League wields more power than Wenger, who recently celebrated 19 years at the Arsenal helm.

Hailed as revolutionary when he first arrived in English football, Wenger can no longer be said to be a pioneer of sports science, medicine and nutrition.

Too many Arsenal players have suffered too many injuries, over too many seasons. The club’s track record is poor in this regard, and Wenger must take a considerable share of the blame.

To attribute injuries as ‘bad luck’, or claim he is ‘not a doctor’, as Wenger often does, is simply passing the buck. He hires the staff and picks the team. He assesses the players in training sessions to see who is in the right condition to play.

Why did he halt Walcott’s warm-up at Hillsborough and wave the player on to the field of play when he was not ready?

Yes, the manager’s decisions are based upon the advice he gets from the fitness and medical staff, as well as the views of the players themselves. But Wenger is a hands-on boss and has the final say on everything.

He is loyal to a fault. By most estimations, he overhauled his fitness team about five years too late, even though Forysthe’s appointment paid immediate dividends.

Which makes the recent injury crisis something of a mystery. What has changed in Wenger’s preparations at Colney?