With Marsh, not only is his footwork weighed down but also his confidence. In isolation, his batting average of 31 after ten Test innings could be plenty worse. However, he finds himself in a situation where all around him have made multiple scores, making his lack of runs an even more glaring tribute to self-doubt. But how bad is his form slump? To find out, w need to frame his scores contextually.
Unfortunately for Marsh, a wide-angle lens does him no favours. Each member of the current Australian top order's batting average had exemplified elements of stabilisation by the tenth innings; by each player's twentieth knock their averages had effectively stabilised. Mike Hussey is of course the outrider after starting his career being exceptionally hard to dismiss.
As one would expect, batting averages tend to steady as the number of innings increases - firstly because you obtain more consistent results and secondly because the player has established themselves as a Test quality player (or not). Trends are easy to spot in such graphs - and Marsh's seems likely to steady at around 30, significantly below the Test batsman's Mendoza line of 40.
Perhaps it's not about youth, it's about situation. Taking all batsmen as equal, the following graph plots Marsh's average since debut with all those batsmen Australia have used.
As you can see, Marsh's form has slipped below that of the particularly unlamented Phil Hughes and even below the spectacularly out of form Brad Haddin. So it's not circumstance either. Marsh simply has plumbed the depths of form not seen since Dean Jones in Pakistan. It's time to move on.
All averages include the first innings from the current Test in Adelaide, but not the second.