Where should Wilshere play? He's no defensive midfielder...
We've long known and worried about Jack's defensive commitments, but that sequence brings it into sharp focus. To take a broader view, in his role as a defensive midfielder, he registered a veritable 2,000,002 score; that is, 2 tackles, 0 interceptions, 0 clearances, 0 effective clearances, 0 shots blocked, 0 offsides-won, and two fouls. Now, some of those are not his fault as a defensive midfielder is rarely in position, for example, to catch an opponent offside. However, contrast that stat-line against the kind that Ramsey frequently delivers when he's in the DM role, when he regularly delivers tackles and interceptions, occasionally leading the squad in one or the other. Without Ramsey and Flamini available, we've had to slot in other players, including Ox, Rosicky, and Jack.
Of the three, Jack seems least-suited to the DM role unless he can learn to commit more thoroughly to the "defensive" element. At this point, unfortunately, this does not appeal to his skill- or mind-sets, which seem to favor picking up the ball and driving forward. His positional sense and tackling are not yet strong enough to allow him to shield the back-four or negate counter-attacks, unless we're willing to credit Jack for fouls that stop play, which I'm not. In the short-term, until the return of Ramsey, we may have little choice but to rely on Jack there. The Arteta-Flamini pairing seems to swing the pendulum too far in the other direction, replacing the defensively-impaired Jack with the offensively-inept Flamini.
The answer, though it may have to wait for the return to fitness of Aaron Ramsey, is to play Jack as a deep-lying central midfielder even if this pushes Özil out to the right. After all, with Walcott out, we have a bit of a gap there to fill as well, and we've seen how Özil has himself struggled in the central role. Allowing him to roam along the flanks a bit might liberate him from some of the pressure he's been under while putting Jack in the middle where he can play as the engine that drives the offense forward. With Rosicky then playing in the DM role, his stronger sense of the role, work-rate, and willingness to press up the field without abandoning his position, such a set-up might restore more of the aggressive push we've lacked in recent weeks.
In the longer term, I see a defensive midfield pairing of Wilshere and Ramsey and salivate. For now, however, Jack doesn't seem ready for the responsibility, at least not against the stronger sides. With Flamini coming back, I'd suggest that he and Jack would work well together, with Flamini barking out instructions to Jack about where to be and how fast to track back. The malaise that has afflicted the squad lately is an issue, and I want Jack on the pitch for his intensity and drive. In fact, with him as a CAM and with Rosicky behind him as a DM, there's a lot of buzzing about that could be available, enough to harass and discombobulate quite a few opponents in weeks to come