German election: Merkel battles Steinbrueck in TV duel
German Chancellor Angela Merkel's main rival in this month's election has accused her of causing misery by imposing austerity on southern Europe.
In their only head-to-head TV debate, centre-left candidate Peer Steinbrueck called her euro policies a failure.
But Mrs Merkel pointed to Germany's healthy economy, calling it "the motor of growth" in Europe.
The event was seen as Mr Steinbrueck's biggest chance to claw back Mrs Merkel's lead in the opinion polls.
The chancellor's conservative coalition is reckoned to be leading Mr Steinbrueck's Social Democrats (SPD) by around 15 points (40% to 25%).
However, even with those figures, Mrs Merkel would still need a coalition partner, meaning the outcome of the election remains uncertain.
With three weeks to go before the 22 September vote, the two candidates were grilled by four journalists before an estimated TV audience of up to 20 million.
Mr Steinbrueck, who was Mrs Merkel's finance minister in the 2005-09 "grand coalition" between left and right, attacked her handling of the European debt crisis.
"I would have followed a different crisis strategy. Of course there must be budget consolidation in these countries, but not a deadly dose," he said.
"Germany once got help too and we must not forget that. Germany was massively helped after the Second World War with the Marshall Plan."
"You voted for everything," Mrs Merkel retorted, pointing out that the SPD had supported her policies in parliament.
Mr Steinbrueck said Germany had the biggest low-pay sector in Europe, and that he wanted to ensure greater "social justice," by introducing a national minimum wage and higher taxes for the biggest earners.
The chancellor said Germany had more people in work than ever.
"We must not do anything to put jobs at risk and the tax hike plans of the Social Democrats and the Greens bring with them the risk that we spoil the good situation that we have instead of improving it."
So far, there have been few campaign issues that have exposed major policy differences between the two figures and the parties have focused on their personalities.
Mr Steinbrueck is often witty but prone to gaffes, while Mrs Merkel often seems less than comfortable in the cut and thrust of live debate, the BBC's Berlin correspondent Stephen Evans reports.
A snap poll for Germany's RTL television declared Merkel a narrow winner of the debate, while an ARD TV poll suggested Mr Steinbrueck had been more convincing.
However, Mr Steinbrueck did not appear to land the sort of knock-out blow that would change the course of the campaign, our correspondent says.
The leaders of the smaller parties taking part in the election will have their own election debate on Monday.
Mr Steinbrueck, 66, has said he will not enter a grand coalition with Mrs Merkel's Christian Democrats.
He would prefer to go into coalition with the Green Party, while Mrs Merkel is hoping to continue her governing alliance with the liberal Free Democrats (FDP).
However, the FDP has lost much of its support since the last election, and if it does poorly Mrs Merkel and Mr Steinbrueck may be forced to work together.