Acelino Freitas

Early success

After the Pan American Games he turned into a professional boxer on July 14, 1995, against Adriano Jose Soares. With his win by knockout in the first round that night, Freitas set off a streak of 29 knockout wins in a row, which places as one of the longest knockout wins streak in boxing history. His first 10 wins were against low level competition, but for fight number 11, he took on the much more experienced Edwin Vazquez, knocking him out in the seventh round.

Between 1997 and 1998, Freitas won four more fights and then took on Francisco Tomas Da Cruz, a former world title challenger of Julio César Chávez. Freitas handled Da Cruz with a knockout in two rounds and then added three more knockout wins before getting his first world title shot.

First World Title

On August 7, 1999, Freitas knocked out WBO Junior Lightweight Champion Anatoly Alexandrov in the first round. Soon after, he signed a contract with cable TV giant Showtime, which began to telecast Freitas' fights to the United States. Freitas then made five defenses of his world title and had one non-title bout, all of which ended in knockout wins. He then went to London and took only 45 seconds to stop Daniel Alicea in another non-title affair. Freitas then beat the former world champion: Al Kotey, the brother of David 'Poison' Kotei, by a ten-round decision.

Freitas vs Casamayor

On January 12, 2002, Freitas decided to sign for a unification bout with the WBA world champion, Joel Casamayor, a Cuban refugee who resides in Florida. In a rousing super featherweight unification title bout battle between unbeaten champions, a controversial knockdown and a blatant foul cost Casamayor his unblemished record and his title as Freitas won a close 12 round unanimous decision.

In a classic boxing confrontation between the Brazilian bomber Freitas (129½) and the Cuban boxer Casamayor (129½), the fighters switched roles midway through their encounter in what was reminiscent of Sugar Ray Leonard's first historic face-off with Thomas "Hitman" Hearns back in 1981. The scientist Casamayor became the aggressive slugger, while the puncher Freitas turned into the boxer as once again the unpredictable transpired in a mega-fight.

A glancing right-hand to the neck of the off-balanced Casamayor in the 3rd round was ruled a knockdown by referee Joe Cortez and intentionally hitting on the break in the 6th saw the Cuban penalized another point. It was the difference in the finale tallies and the two point cushion that the tiring Freitas retained across the boards on all three judges scorecards. Ring officials Robert Byrd, Bill Graham and Dave Moretti having identical scores of 114 to 112 for the Brazilian.

After Casamayor

Next, he went to Phoenix, to fight Nigerian Daniel Attah, with only the WBO belt on the line, winning a 12-round decision on August 3, 2002.

Freitas then retained the title in Chicago with a fourth-round knockout of Juan Carlos Ramirez. On August 9, 2003, he and Jorge Barrios engaged in what Showtime commentator Steve Albert called a candidate for fight of the year. Freitas was floored in rounds eight and eleven, but retaliated with a knockdown of his own towards the end of the eleventh, and ended up retaining the title by knockout in round twelve.

Freitas began 2004 by winning a 12-round unanimous decision over Artur Grigorian on January 4, to become the WBO's world Lightweight champion. On February 1 of that year, the WBA announced it had named Freitas their 2003 Fighter of the year.

Freitas vs Corrales

On August 7, 2004, Freitas lost for the first time, losing his WBO Lightweight title to Diego Corrales by quitting in the tenth round after being knocked down by a left hook in Connecticut.

After Corrales

On April 29, 2006, Freitas defeated Zahir Raheem for the vacant WBO lightweight title by split decision. Freitas announced his retirement as a professional boxer on October 4, 2006.^[3] Later on, he announced his come back from retirement, and the WBO re-instated him as their lightweight champion.

On April 28, 2007, he fought Juan Diaz in Mashantucket, USA, losing by TKO after quitting on his stool before beginning the 9th round, drawing boos from the crowd.

He has fought three times since his last loss (2012, 2015, and most recently in November 2017), all wins against inferior competition and all in South America (two wins by knockout and one win by 8-round unanimous decision).