NEWARK, N.J. - A private probe into the 2009 death of former boxing champion Arturo Gatti will disprove the official conclusion that it was a suicide, Gatti's former manager said Tuesday.

Gatti, a popular junior welterweight champion who retired in 2007 with a career record of 40 wins and nine losses, was found in July 2009 at an apartment he and his family had rented in the Brazilian seaside resort of Porto de Galihnas.

Brazilian police initially considered Gatti's wife, Amanda Rodrigues, a prime suspect and arrested her for his murder but released her a few weeks later. They eventually concluded after an autopsy that Gatti hanged himself with a handbag strap from a wooden staircase column in their apartment.

Former manager Pat Lynch said Tuesday he hired Paul Ciolino, a private investigator from Chicago, about 10 months ago to take a new look at the case. He said the results of the investigation would be released at a news conference at the end of this month.

"There were too many things that were left open, too many unanswered questions," Lynch said. "I just wanted to find out what happened that night. No one's going to convince me he took his own life."

Ciolino, who also has examined the Amanda Knox murder case as a consultant for CBS' "48 Hours," said he believes Gatti's death was not a suicide and called the Brazilian investigation "inadequate and downright incompetent." Ciolino didn't give details about his investigation but said when its findings are presented, "there will be little doubt as to what happened."

Questions surrounding Gatti's death prompted a second autopsy conducted at the request of the boxer's family in Canada in 2009. Michael Baden, former chief pathologist for the New York state police and host of the HBO show "Autopsy," observed the procedure on behalf of the family and said coroners didn't rule out homicide as a cause of death.

The Italian-born, Montreal-raised Gatti developed a large following in New Jersey, where he lived and trained beginning in the early 1990s. Nicknamed "Thunder," he fought some of his most memorable fights at Atlantic City's Boardwalk Hall, including a trilogy of slugfests with fellow 140-pounder Micky Ward beginning in 2002 that endeared him to fans.

The Jersey Journal first reported the private investigation in its Tuesday editions.