The Shawcross Redemption.

Stoke fans are restless again.

A couple of weeks after eagerly anticipating a Wembley trip and making a push for a domestic cup double, settling for 4th place in the Premier League and regular trips to the Nou Camp, while fighting off the advances of Chelsea and Manchester United for the services of Mark Hughes, they've seen all this fade to grey.

They're now wondering how Hughes could be so inept as to neglect Stoke's defensive and attacking frailties in the January window and when he should go to avoid regular trips to the Pirelli Stadium, Burton.

Knee jerk punditry has nothing on those with an emotional and financial investment.

Top of Hughes' current rap sheet in the eyes of his previously greatest supporters is his neglect of adequate cover for the central defence.

It probably doesn't help that on the same weekend that Robert Huth (allowed to leave on a free) was visibly winning the title for Leicester, Stoke captain Ryan Shawcross was again sitting out a tame home defeat to Everton through another injury.

With Huth & Shawcross in tandem, Stoke often dispensed with the services of a keeper.

With or without stats are horribly blunt devices, where small win/loss samples can "prove" bit players essential to a side's well being, when they are merely the coincidence with little causation.

But just as action or heat maps for a single match for more numerous in game stats may shed some light on where a side won or lost a single game, aggregating such things as the quantity and quality of chances allowed with or without a particular player may also tell us something about their impact.

Shawcross has obligingly missed about half the season through injury and the odd suspension. Here's the expected goals per 90 that Stoke have allowed when he's played and when he hasn't in the Premier League. (excuse the familiarity in the table, it was done for a Stoke fan site).

So there is tentative evidence that a player who has had his fair share of media scrutiny has become an important, if not irreplaceable part of Stoke's defence.

His most obvious attribute is his strength in the air and his ability to prevent attackers winning the aerial challenges (often, and in keeping with many defenders, by anchoring the attacker to the ground by his shirt tails).

If you look at the number and proportion of headed chances conceded when Shawcross is and isn't on the field again the contrast is marked. 20% of the total attempts come from headers in his absence of which five have resulted in goals compared to nearer 10% when he plays, with no goals conceded.

It has been suggested that the skill differential when players use their head is greater between players than when they use their best foot, so for once the fans may actually have a point when they debate that Stoke have one of the Premier League's best defensive headers of the ball, but nothing in the way of cover.