New Tory leader Michael Howard has clashed with Tony Blair about the past and accused the government of ineptitude in its running of services.
In his first outing at prime minister's questions since succeeding Iain Duncan Smith, Mr Howard tackled Mr Blair over the spiralling cost of red tape.
Mr Howard was greeted with enthusiastic cheers by MPs on the Tory benches amid an electric atmosphere in the Commons.
Mr Blair responded by attacking Mr Howard's role in the poll tax.
The prime minister welcomed Mr Howard to the despatch box saying that he was pleased that the Tory leader had the opportunity to rehabilitate himself politically having been, he said, discredited when he was a minister.
He then zoomed in on Mr Howard's role, when a minister under Margaret Thatcher, in the introduction of the poll tax and the Tory party's economic record when in government.
"You don't simply represent the past. You would take us back to the past,"
he told Mr Howard.
"Same old people. Same old policies. Same old Tories."
Mr Howard said he was happy to debate the past, recalling Mr Blair's own past position backing UK withdrawal from the EU and his criticism of US foreign policy.
But he said the British people would prefer it if he took every opportunity to remind Mr Blair of the "failures" of his current government.
After Mr Blair's answers to questions about the rise in the running costs of the NHS and then the Treasury Mr Howard said: "Two questions asked, neither answered - not a very good start, I'm afraid.
"The fact is that administration costs at the Treasury have gone up by 52%. Since you became Prime Minister the cost of running Government departments has gone up by 50% - that's nearly £7bn a year.
"Isn't that eloquent testimony to the ineffectiveness, ineptitude and sheer incompetence of this Government - all at the expense of the hard-pressed British taxpayer?"
Mr Howard and Mr Blair frequently clashed when the prime minister was an opposition spokesman for Labour and the Tory leader was home secretary.
It was when Mr Blair was Mr Howard's opposite number that he coined Labour's "tough on crime, tough on the causes of crime" slogan.
Crime figures, terrorism and the minimum wage were among the issues which featured in their Commons jousts when it was Mr Blair who was pursuing office.
Tim Allan, former deputy press secretary at Downing Street, said recently: "They respected each other. They each managed to score points against each other."
As shadow chancellor, Mr Howard has seemed to relish big set piece debates in the Commons, often trying to highlight splits between the prime minister and Mr Brown.
The new Tory leader has spent the week unveiling his new shadow team and restructuring his party for the run-up to the next general election.
On Tuesday, the Conservative board decided the Tories would move out of Central Office - their headquarters in Westminster since the 1950s.
Blair has acknowledged Howard's debating skills
They plan to sell the lease as soon as possible and find more suitable premises.
Shadow home secretary David Davis said the party wanted somewhere with open plan offices and facilities such as a television and press centre.
The decision is also a symbolic move away from a building which in recent years has become heavily associated with plotting and back-biting against the leadership.
Mr Howard's reshuffle is also designed to produce a team battle-fit for the election campaign.
He has slashed the size of the shadow cabinet by more than half to 12 - although in total he has given jobs to more than 100 MPs.