It’s hard to recall a budget in the modern era that has been delivered by so wounded and humiliated a treasurer. It now appears to be open season on Joe Hockey even before he stands up to deliver the government’s second budget tomorrow night.

The embarrassment for Hockey yesterday, of fronting the key pre-budget interview with Laurie Oakes and not being able to discuss the centrepiece of the budget, despite the childcare announcement having been lavished on News Corp’s Sunday tabloids, was bad enough. But the Treasurer was also given the task of revealing the downside of the package — that women who had access to employer-funded childcare would be punished for “double-dipping” and not be eligible for taxpayer-funded parental leave.

Suddenly the reason for Hockey’s poor body language in recent days is clear. There has plainly been a decision by Tony Abbott and his office to reward Scott Morrison at the expense of Hockey, who looks increasingly as if he is being lined up to take the fall if the budget fails to deliver a revival for Abbott. The News Corp newspapers have clearly been given the green light to go after the Treasurer. And this morning, astonishingly, Morrison compared Hockey to Greg Bird, a rugby league player of ill repute who is currently sidelined during the most important part of the rugby league calendar.

But if Abbott thinks he can simply offload his Treasurer at his convenience, he’s wrong. An effective treasurer is a core part of an effective government. For however long a wounded and humiliated Hockey continues to occupy the role, the government will under-perform. And what if Hockey decides he’s not going to go quietly? The treatment of Hockey is worse than shabby — it looks profoundly ill-advised.