Robson Conceicao tested Oscar Valdez in the Brazilian boxer’s first world title fight four months ago.

The 2016 Olympian’s performance versus Valdez validated that he is a credible contender in the 130-pound division and moved him into another high-stakes fight against Xavier Martinez on Saturday night. Conceicao still wishes the 12-round, 130-pound championship match he lost by unanimous decision never happened.

Conceicao would’ve preferred that the WBC made an “example” of Valdez for failing a performance-enhancing drug test a little less than a month before he encountered Conceicao on September 10 in Tucson, Arizona. Instead, Valdez and his promoter, Bob Arum’s Top Rank Inc., utilized a loophole in boxing’s unified PED testing procedure to move forward with his first defense of the WBC super featherweight championship that the unbeaten Mexican veteran won in his previous bout – an impressive, 10th-round knockout of favored rival Miguel Berchelt last February 20 at MGM Grand Conference Center in Las Vegas.

According to Conceicao, allowing Valdez to fight despite his violation of the WBC’s “Clean Boxing Program” sent a damaging message to both boxers and fans alike.

“Before that happened, I was a big fan of Valdez,” Conceicao told BoxingScene.com. “I respected and admired him a lot. But when he tested positive, everything changed. I was so disappointed with Valdez. In my opinion, when he tested positive, he needed a harsh punishment, to be made an example to the people. They should not let him fight and make a bad example to other fighters.”

Conceicao clearly benefitted from fighting for a world title, financially and from the exposure he received. If it were up to him, however, Valdez would remain sidelined to this day after testing positive for Phentermine, a stimulant banned by the Voluntary Anti-Doping Association.

“I got an opportunity, but I would’ve preferred that Valdez got punished,” Conceicao said. “He should’ve been banned for at least one year from the sport. Then he could come back clean and start again, to be an example.”

The Pascua Yaqui Tribe Athletic Commission licensed Valdez despite his dirty “A” and “B” samples submitted August 13 because it is affiliated with the Association of Boxing Commissions, which adheres to the World Anti-Doping Agency’s testing standards for PEDs. Phentermine is not on WADA’s list of banned substances, thus Valdez was eligible to defend his title against Conceicao in a regulated event ESPN+ streamed from Casino del Sol in Tucson, Arizona.

That understandably caused controversy because Valdez and Conceicao willingly signed up for the WBC’s “Clean Boxing Program,” which is administered by VADA. Mauricio Sulaiman, president of the WBC, publicly defended Valdez and that sanctioning organization’s decision to allow him to defend his title even though he didn’t meet the standards established by its chosen testing partner.

Sacramento’s Martinez (17-0, 11 KOs), who will face Conceicao (16-1, 8 KOs) in a 10-round main event ESPN will televise Saturday night from Hard Rock Hotel & Casino in Tulsa, Oklahoma (10 p.m. ET), understands why Conceicao went through with his fight against Valdez.

“We just wanna fight, you know, and provide for our families,” Martinez told BoxingScene.com. “I think for them to go through with it, if it was anybody else [other than Valdez], it would’ve been a whole different story. They probably would’ve really, you know, punished him. I don’t know why they didn’t do it to Valdez, but it is what it is.”

Martinez, 24, is confident, though, that regulatory agencies, promoters and some boxers themselves have done a better job of policing PED use in boxing in recent years.

“I think it’s come a long way,” Martinez said. “I think back in the day a lot of fighters were probably on a lot of stuff. I think boxing is starting to stay on top of it more. I had my first WBC random drug test [recently] and it tripped me out. I got a hard knock on my door [at home] and it was like, ‘It’s time for you to test.’ I was like, ‘Whoa!’ So, they’re taking it very seriously.”

The Martinez-Conceicao winner will secure himself another high-profile fight later this year. They’re both promoted by Top Rank, which is heavily invested in the 130-pound division.

The top two junior lightweights that Top Rank promotes – Valdez (30-0, 23 KOs) and WBO champion Shakur Stevenson (17-0, 9 KOs) – have agreed to meet in a 12-round title unification fight April 30 at MGM Grand Garden Arena in Las Vegas. Conceicao expects the skillful, left-handed Stevenson to have a “very easy” time with Valdez on his way to winning a wide unanimous decision.

When asked to elaborate, Conceicao replied, “Because I’m not a big fan anymore of Valdez. I don’t like Valdez.”

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.