Rio De Janeiro: Brazil's presidential contenders squared off in an acrimonious debate Thursday, trading barbs about corruption, nepotism and the ability to spark the stagnant economy.

President Dilma Rousseff and her opposition rival, Aecio Neves, are deadlocked in opinion polls less than two weeks ahead of the Oct. 26 runoff election.

Both clearly showed they are moving the race into a more combative phase.

Rousseff leveled charges that Neves put family members into cushy government jobs when he was governor of Brazil's second-largest state. Neves fired back that the president's brother was employed in a “phantom” government job, receiving pay but not showing up for work.

Rousseff also made an indirect reference to an episode in 2011 when Neves was stopped in Rio de Janeiro at a police blitz looking for drunk drivers, during which he exercised his legal right to decline a breath test and was driving with an expired license.

“Have the courage to at least ask the question directly,” Neves angrily shot back.

“Yes, there was an episode in which I refused to take a breath test. My license was expired,” he said. “I regret it, unlike you, who regrets nothing. Let's talk about serious things; it's impossible for you to carry out a dirtier campaign than you already have.”

Neves then returned to hammering away at a growing kickback scandal at the state-run oil company, Petrobras, where a former top executive has told investigators he helped operate a long-running scheme that funneled money back to Rousseff's Workers' Party.

The president said that an investigation is taking place under her government's watch and that no Brazilian leader has fought corruption more than she has, including her forcing out several of her own ministers early in her term after allegations of corruption surfaced against them.

“For the first time, Brazil is systematically combatting corruption,” Rousseff said, arguing that when her rival's Social Democracy Party held the presidency in 1995-2003, investigations into corruption were squashed.

Rousseff won the most votes in the first-round ballot earlier this month, but didn't win the outright majority needed to avoid a runoff. Neves staged a surprising comeback in the days ahead of the first vote to come in second and get into the second-round ballot.

Neves, a two-term governor in Minas Gerais state who left that office in 2010 with a 92 percent approval rating, railed against Rousseff's management of the economy, which has grown at less than 2 percent annually over the past four years and is now in a recession.

After the debate, both candidates were allowed a few minutes to field follow-up questions from journalists at the SBT network that aired the encounter.

Rousseff appeared light headed a few seconds into the questioning, and had difficultly responding to questions.

She sat down, was handed a juice, and wasn't able to answer any more questions as each candidate was allotted the same amount of air time and hers had passed. SBT journalists said the leader quickly recovered after resting.