SAO PAULO - Joaquim Barbosa -- a former Supreme Court justice seen as a potential heavyweight in Brazil's presidential race this year -- announced Tuesday that he will not be a candidate.
Barbosa, who if elected would become the first black president in modern Brazil, tweeted that he had decided against competing "after weeks of much reflection."
"It's decided," he said. "I finally came to a decision. I will not be a candidate for president of the republic. The decision is purely personal."
Barbosa, 63, had been touted as having a real chance at winning in the October 7 election, despite having no experience in electoral politics.
While serving as the Supreme Court's first black justice, Barbosa earned a reputation as a major anti-corruption fighter, lending him instant credibility at a time when much of the political establishment is mired in the giant "Car Wash" graft scandal.
Amid pressure on him to decide whether he was making a run, Barbosa joined the centrist Brazilian Socialist Party in April, beating a deadline for would-be candidates to list a party affiliation.
Opinion polls showed him with surprisingly strong results despite not having campaigned at all.