Arsenal go into Sunday’s north London derby without Jack Wilshere – but the midfielder’s injury opens the door for the Gunners to unleash their secret weapon.

Kim Kallstrom has been largely forgotten since the bizarre circumstances of his arrival at the Emirates just before the close of the January transfer window.

The Swedish international was signed on loan from Lyon despite the sudden discovery that he had sustained a back injury and would be unable to play until mid-March.

It seemed highly illogical to bring him in as cover for the likes of Wilshere and Aaron Ramsey – but now, with the England midfielder sidelined again and Mesut Ozil nursing a hamstring strain, it could yet prove to be a masterstroke.

Kallstrom is likely to be pitched in at the deep end for his Gunners debut at White Hart Lane, while Ramsey – out since the end of December with a thigh injury – may also make his comeback.

This is the beginning of a crunch period for Arsenal, with the back-to-back derbies at Tottenham and Chelsea immediately followed by home matches against Swansea and Manchester City in the space of four days.

Their advance to the FA Cup semi-final means they must reschedule another Premier League fixture, at home to West Ham – so it is likely that an extra option in midfield will be vital.

Manager Arsene Wenger has confirmed he does not expect Wilshere, who sustained a hairline fracture in his foot while on international duty against Denmark last week, to take the field again until May.

That leaves the door wide open for the experienced Kallstrom to do the job he was signed to do, and Sunday’s clash with Spurs seems as good a time as any.

The return of Ramsey – undoubtedly the star of the first half of the Gunners’ season – is also timely, particularly as one or two of his midfield colleagues appear to have gone off the boil in recent games.

Wenger will be hoping that the Welshman can again galvanise his team-mates to recapture their form of the autumn, when as a unit they frequently looked unstoppable.

That is a habit Arsenal need to rediscover now as they head into a series of games that may determine whether they are still chasing the league title by the time Wilshere returns to action.