A body broken at the beginning, a mind snapped at the end, and some rapid healing needed now for an Arsenal squad that is hurting. First, Eduardo da Silva’s broken leg, then a self-inflicted injury: missed chances and mistakes allowing Birmingham City to pinch a point.

Out of the Carling Cup and FA Cup in embarrassing fashion, unlucky not to beat AC Milan last week and now without the Croatia striker for the rest of the season, might Arsenal sulk themselves into second place? Not if Arsène Wenger, the manager is right about the preternatural maturity of his young side — and it has been evident for nearly all of the season.

But when their 30-year-old captain behaves childishly, you have to wonder. The memory of William Gallas’s antics will lingers, as will the images of Eduardo’s shattered leg in the minds of his team-mates, several of whom were clearly traumatised by the injury.

“Everything has been going wrong and we need to recover quickly ,” Nicklas Bendtner, the forward, said. “We can’t keep thinking about this day because it has just been terrible.”

When a penalty was awarded in injury time to Birmingham, Gallas stalked away as if the final whistle had gone, watching from the other half of the pitch as the kick was taken, then lashing out at an advertising hoarding.

A bitter reaction to the pain of failing to win for a fallen team-mate and a reminder of the mental toll that the title race can take — as if it was needed on a day when Sir Alex Ferguson came up against Kevin Keegan.

Gallas looked like he was mourning the end of Arsenal’s hopes, yet his team had gone six points clear before Manchester United’s thrashing of Newcastle United reduced the Londoners’ lead to three with 11 games left.

A sense of injustice can be the most powerful of motivations, of course, but it brings a dangerous volatility. Manchester United’s players are more experienced, look more efficient and, in the verbal contests, Ferguson is never short of a box of matches if he senses that the fireworks have arrived.

Nobody can doubt Wenger’s shrewdness, but the aesthete can turn acerbic, as his hyperbolic call for Martin Taylor to be banned for life showed. He also airbrushed away Gallas’s behaviour, suggesting that attention should instead focus on “real problems” — the referee’s errors and Taylor’s tackle — and apparently missing the potential hypocrisy in lambasting Taylor for his uncontrolled aggression while sympathising with Gallas’s fury. Gallas’s actions were certainly the product of passion. Passion channelled not for positive purposes, though, but in a futile gesture of dissent.

Wenger’s underreactions to petulance from his own and his overreactions when opponents cross the line are nothing new. Often tactical, at St Andrew’s they seemed born of emotion. But whatever happens in private, is this the sort of parental indulgence that just invites more ill-discipline? And can Arsenal afford to be anything other than clear-headed as the campaign enters the business end?

The injury dwarfed the only good news, Theo Walcott’s double, his first league goals for the club on his 31st appearance. It also masked some latent concerns that have floated under the surface of Arsenal’s season like jellyfish in a tranquil sea.

With Robin van Persie’s return at least a fortnight away, Eduardo’s absence increases the importance of Bendtner, who has scored once in the league from 15 substitute appearances and one start. Emmanuel Adebayor clashed with Bendtner in the 5-1 Carling Cup semi-final defeat by Tottenham Hotspur a month ago, and their relationship may not have been enhanced on Saturday. Adebayor did not square the ball to Bendtner when clean through in the second half. Adebayor’s shot was saved by Maik Taylor and Bendtner looked exasperated that he had not been given the easiest of chances to score Arsenal’s third.