Brazil's presidential contenders are squaring off in another debate 10 days ahead of voting in the deadlocked race.

President Dilma Rousseff and rival Aecio Neves are fighting to win over voters ahead of the Oct. 26 runoff ballot.

Thursday's debate is centering on what have emerged as the top two issues: how to turn around Brazil's fledgling economy and who would best battle corruption.

The center-right Neves of the Social Democracy Party sharply questioned Rousseff about a growing kickback scandal at state-run oil company Petrobras. A former top-ranking executive has told investigators the governing Workers' Party benefited from the scheme, which it denies.

Rousseff shot back that she has battled corruption, including forcing out several of her own Cabinet ministers early in her term after corruption accusations surfaced against them.