He must have wondered if this day would ever come too. He leads on Afghanistan and the Kabul Conference. He probes the commitment to troop withdrawal. Clegg claims to be the first Liberal at PMQs since the 1920s – about the same time that Straw joined the shadow cabinet. Not a bad joke.

Not sure they had PMQs in the 1920s, but anyway. Straw comes back, saying it is his one and only appearance. He puts in the boot on Sheffield Forgemasters, and puts Clegg on the spot. Clegg says the troops will be home by 2015. He says the loan was ‘one of affordability’, and that Lord Mandelson was writing cheques that would bounce.

Straw mocks Clegg’s inability to be open and transparent about the dilution of the company’s shareholding. Not a question, but a dissertation says Clegg. He quotes a worker from the firm, but is shut up by Bercow for being too ‘discursive’. Straw asks why he supports a £550m tax break for married couples, but not a loan to Sheffield Forgemasters? Clegg quotes again from Mandelson’s memoir.

Straw comes back with a quote from Lord Ashcroft about the lack of influence of Lib Dems on the coalition government. Straw is now shouting himself hoarse. This will look and sound terrible on the news bulletins. Clegg says Straw needs to go away and practice.

Confusion reigns as Straw has asked five questions, but Bercow thinks it’s six. Straw is shouting again. Clegg sounds calm, and accuses Straw over Iraq. Though it pains me to say it, I think Clegg has bested Straw in this week’s one-off contest.

Former NUM boss Ian Lavery speaks up for his constituents in the north east. Clegg just waffles, and repeats his mantra that it’s all Labour’s fault.

He’s challenged over the rise on VAT by the leader of Plaid Cymru, but claims he had to do it when he saw the size of the structural deficit. Kate Green, surely a future Labour Cabinet minister, asks a grown-up question about a constituent on disability living allowance. She’s my backbencher of the week.

Julian Huppert, the Cambridge MP, says Clegg is the first Liberal since Lloyd George to answer questions. It’s a planted question about the closure of the Yarlswood detention centre. Jeremy Corbyn, nothing if not consistent, calls for an end to UK/US military engagement in Afghanistan. Clegg repeats that no soldier will be in a combat role by 2015.

There are two political narratives clashing this week – and for the rest of the parliament, probably: ‘It’s all Labour’s fault for overspending’, versus ‘The Liberal Democrats are propping up a right-wing Tory government.’