These exchanges are all about momentum and the momentum was with Ed Miliband right from the moment John Major sat down at the press gallery lunch yesterday.
Major's call for Cameron to take on the big six energy companies gave the Labour leader a target so wide he could have hit it blindfolded and hobbled. In the past Miliband has demonstrated an extraordinary skill to miss these kinds of targets anyway, but for once that skill was absent.
"The prime minister said that anyone who wanted to intervene in the energy markets is living in a Marxist universe," Miliband began.
"Can he tell the House how he feels now that the red peril has claimed John Major".
The red peril quickly descended on Cameron as well.
It's not surprising Ed Miliband wants to talk about the former prime minister, given the mess Labour made after he left, replied Cameron, his face already reddening.
"Of course, John Major was a Conservative prime minister who won a majority, unlike this one," quipped Miliband in return. This was a simple point and basically unanswerable. The Tory benches remained remarkably quiet.
By now the red peril had all but consumed the prime minister's face. From this point Cameron had two choices. He could either go on the attack against Miliband personally or focus on the issue and try to win that battle instead.
In the event he tried and failed to do both. His claims to want to "roll back" green taxes were immediately contradicted by Miliband, who pointed out that the Lib Dem energy secretary had already ruled this out. And his attacks on Miliband as a "con man" backfired after the Speaker described them as "unparliamentary" and out of order.
Cameron looked increasingly out of sorts and rattled, while Miliband remained remarkably calm and confident throughout.
This was the third week that Miliband has focused on energy bills. By now the prime minister really should have come up with a decent response. If anything he seemed less well prepared than previous weeks.
For months now, Cameron has tried to paint Miliband as weak and un-prime ministerial. Today he looked increasingly like that himself.
Verdict: Miliband 3, Cameron 1