The problem with a table that only has two sturdy legs when it should have six, is obvious. For an illustration, take a look at the New Zealand batting line-up. Without Brendon McCullum and Ross Taylor they are as thin as a chiffon scarf and even with them, they're missing at least one layer of extra lining.
Balance. It's a term that's often used to describe the correct make-up of a cricket team. Most teams veer on the side of top-heavy when they are off balance, but New Zealand appear to have gone the other way. There is method in their four-pronged seam approach and intent that is laudable but the cost to the batting department has been severe.
One opener, Rob Nicol, has endured such a torrid time at the crease that his suitability to the longest form of the game is having serious questions asked of it. His partner, Martin Guptill, has hit a sudden slump after a golden run of form. All this means that McCullum pretty much has to face the new ball.
That leaves a situation where he has to fight it out and form a stand with Taylor in order for New Zealand to stabilise. Even if they do, they continually sit on the edge of the cliff, knowing that if one of their two mainstays gives way, it will expose the less experienced Kane Williamson. After him there isn't much in the way of specialist batsmen to come.
Against an attack the New Zealand team have themselves called the best in the world, expecting a sizeable total from a combination like that is a big ask. "With us having five batters they've come in and set pretty defensive fields so I think we've got to find a way of being able to try and rotate the strike and get off strike as well," Taylor said. "They're bowling a lot more maidens than us and I think that's an area we need to address as well with the ball."
South Africa sent down 33 maidens in their 129 overs across two innings, while New Zealand managed 21 in their 98 overs, which is comparably not much worse. What New Zealand did not do as well as South Africa was set fields that could allow bowlers to work to plans with the same precision Graeme Smith did or create the same amount of pressure through consistency of good deliveries.
Although New Zealand's bowlers are rightly proud of their effort in bowling South Africa out relatively cheaply in the first innings of both Tests, Taylor acknowledged that the batting failures have left the bowlers needing to do even more. "When we go in with that side we need to take 20 wickets and it does put a lot of pressure on the batsmen as well," he said.
The solution seems to present itself, New Zealand have to include an extra batsman to fix the lopsidedness of their line-up. The place for that batsman appears at the top, probably where Nicol has been occupying space which McCullum should be in so someone else can come into the middle order. Taylor said that would not happen. McCullum would be left at No. 3 "at this stage."
Dean Brownlie, who broke his finger against Zimbabwe, will have his first game back this weekend and if fit, could come into the side. Where he would fit in is unclear. Daniel Flynn, who has scored 461 runs in four Plunket Shield matches including two centuries in his last two games, is being talked about as a candidate for the opening berth and the only way to accommodate Brownlie would be to push Daniel Vettori to No. 7 and leave out one of the bowlers, which Taylor seems loathe to do.
"You've got to play aggressively," he said. "Without weather interruptions there's not a lot of drawn cricket in Test matches these days, especially in New Zealand. We have to play aggressively. We're one-nil down in the series and we have to try and draw the series. We're eighth in the world and we want to get up those rankings and you don't get up by drawing Test matches or losing."
His opposite number, Graeme Smith, hinted that aggression may be misplaced because it allows South Africa to sit, just gently on the table and break it. "They take that risk playing Dan (Vettori) as an allrounder at six. They play a lot of bowlers, four seamers and a spinner so they obviously take a more aggressive option with their bowling attack," he said. "That will weaken their batting. Their tail is an area we would like to get into and exploit."
Edited by Kanishkaa Balachandran

Firdose Moonda is ESPNcricinfo's South Africa correspondent