As John Stones was carried off at Old Trafford on both a stretcher and a wave of Evertonian misery, there was a sense of inevitability. Typical, we all thought, had to be Stones. As I imagined him hobbling along to join four other key players (Ross Barkley, Seamus Coleman, James McCarthy and Kevin Mirallas) in the treatment room, a daunting thought regarding Roberto Martinez struck me. Didn't this sort of thing happen all the time at Wigan? Isn't this why they were relegated? Is an extensive injury list a feature of his management?

Martinez’s physiotherapy degree informs a unique approach to fitness vindicated by never having been injured "for more than nine weeks in 16 years" as he told the Daily Mail’s Matt Lawton. Years ago, he did tell the BBC about a rupture of his “medial ligament” which kept him “away from the field for four months” but few major injuries, that’s the gist. Martinez focuses on football-related fitness as opposed to gym work, running and shock and awe pre-seasons. Gradually developing long-term fitness is the aim. On this front, it's worth noting that Everton won nine of their final 12 games last season, transforming a decent season into their Premier League best. Similarly however, Wigan basically only ever stayed up because of this sort of thing, 2012’s seven wins in nine their pinnacle. Struggling to get up to speed, finishing strongly – this is so far the pattern.

"We have to have so many different partnerships and keep changing, and that caused us problems" – Martinez’s assessment after Wigan’s relegation which accurately depicts Everton’s defence. Stones’ ankle rupture makes it 16 centre-back injuries under Martinez (according to PhsyioRoom.com). Everton’s new, old partnership of Phil Jagielka and Sylvain Distin have accounted for 11 of them. If one gets injured, Antolin Alcaraz, of one game every two months fame, is holding the fort, along with capable but inexperienced Tyias Browning. Unlike relatively interchangeable attackers, defenders thrive on the sort of familiarity consistently denied under Martinez. This is a framework for defensive struggle.

The effect on performance is harrowing. Evertonians of a paranoiac cynicism, look away now. During Martinez’s four Wigan years, the Latics conceded 275 league goals (!) - just under 69 per season, 1.8 per game. Scarily, these eye-poppingly awful statistics are actually better than Everton’s current 2.3 goals per game campaign (!!), although this seven-match sample neglects last season’s 1.0 average, bettered only by Man City and Chelsea. By this stage of Wigan’s injury-ravaged relegation campaign, they’d conceded 13. Depleted or not, Everton have allowed four more. Martinez’s defences suffer many injuries and concede a lot of goals - this is characteristic of his Premier League career.

The fittest team

Martinez works completely differently to predecessor David Moyes: “You need to work with the ball [to] get the footballer fit. It’s pointless to run and run or do an exercise not linked to football – it's not going to get you fitter.” A typical training week involves a “48-hour, post-game recovery period, two training sessions, another active recovery and then […] three sessions to focus on the game” – all shifted around differing match times. Uphill excursions, double sessions and vomiting players were a feature of Moyes’ pre-seasons. Former midfielder Lee Carsley once revealed Moyes led a full session every Monday as other teams rested: “he would say, 'No one else is doing this now, that's why we're the fittest team' – that’s why mentally, we could cope with anything”. So how do their injury records compare?

Moyes averaged 48 injuries per year in his last six Everton seasons. This figure rose to 58 in Martinez’s first campaign (again, according to PhysioRoom.com). Moyes kept more players available though he did average 60 injuries in his first five years suggesting longevity was a beneficial factor. Besides, an absence of injury does not necessarily constitute an abundance of fitness. The increase in tempo and impetus, and mass introduction of youngsters under Martinez, has made Everton faster and more athletic, scorers of late goals rather than conceders. Moyes’ teams were physically robust but fatigued; Martinez’s are energetic but susceptible to injury; the latter has more aerobically dynamic players available less often, but did, let’s not forget, set a new a Premier League winning streak and points total in his first season.

One of the Spaniard’s long-held beliefs that “every injury can be avoided” rang hollow as Kevin Mirallas limped off with the 14th hamstring injury of Martinez’s tenure. Not all were as bad as Mirallas’ but many were. I’ve written too many disparaging tweets about Arsene Wenger’s injury record to overlook that. Injuries vary and occur sporadically but when the same ones crop up repeatedly, the lens must focus on the manager’s influence. A near one-a-month hamstring injury record is sufficient for a top-to-bottom review of your hamstring-prevention policy. As with Wenger, there’s a point where physical suffering bears rotten psychological fruit: can players really trust methods which consistently result in injury? Doesn’t a packed treatment room breed fear over time?

Martinez believes “the way you look after yourself over 24 hours is more important than what you can do in training”. He lists three steps which “every professional sportsperson should live by”: “Sleep for a minimum of eight hours a night […] eat properly - avoid fatty, fried food - at least three times during the day […] and train at 110%”. Martinez was physiologically and nutritionally aware from a young age, applying theory to his diet to aid both university studies and a burgeoning football career, and only ever sampled alcohol on his wedding day. He may reasonably hope to impart his knowledge to players, but his informed devotion is unlikely to be matched; what worked for Martinez may not necessarily work for his players.

Amplified by uncertainty

Injury-enforced rotation dictates an in-and-out selection policy for Martinez which is much more suited to impact-dependant attacking. Accordingly, his teams’ goals scored total has risen every year since 2009: 35, 40, 42, 47, 61. 13 goals in seven matches leave Everton on course to maintain that record. However, defenders’ optimum performances have a lot to do with routine. Individual errors can be limited, passing solutions can be found with the aid of familiarity. Martinez’s style demands defenders take risks, risks that are either managed by memory or amplified by uncertainty. Near- constant injuries will only ever result in the latter.

Six of Everton’s eight currently injured players should be returning soon to leave just Mirallas and Stones on the sidelines. This almost fully-fit squad, a couple of weeks away at least you’d imagine, permits a chance to extend this close-up inspection of Martinez. If he’s just been unlucky since arriving at Goodison, and with many incidents he certainly has, that worryingly high injury rate should begin to come down. If however it doesn’t, Everton will have a serious problem on their hands.