By Keith Idec

Liam Smith doesn’t believe Canelo Alvarez’s explanation for how clenbuterol turned up in his system.

The former WBO super welterweight champion cannot see other skeptics accepting the Mexican superstar’s story, either.

No matter how many times Alvarez tests negative for performance-enhancing drugs moving forward, Smith assumes most boxing fans won’t forgive Alvarez for testing positive twice last month for a banned substance.

Alvarez claims clenbuterol was in his system due to contaminated meat. Mexican boxers Erik Morales and Francisco Vargas also have blamed contaminated meat for their positive tests for clenbuterol, but Smith deems that too convenient of an excuse for Alvarez.

“Regardless of my loss to him, I’m a fan and I think it ruined his legacy,” Smith told iFL TV during an interview posted Sunday to its YouTube page. “I think he’s an unbelievable fighter, doesn’t need to do anything like that. On ability alone, he’s one of the best about. I think he’s probably ruined his reputation to a lot of people who won’t change their tune. Even if he gets cleared of it, people will still have their own opinion.”

England’s Smith (26-1-1, 14 KOs), who was knocked out by Alvarez (49-1-2, 34 KOs) in the ninth round of their title fight 18 months ago, also questioned the changes in Alvarez’s physique since they fought in September 2016. Since beating Smith in a 154-pound championship match, Alvarez has fought Mexican rival Julio Cesar Chavez Jr. at a catch weight of 164 pounds and Golovkin in a 160-pound title fight.

“If you look at the body, from the fight with me until the fight with Golovkin,” Smith said, “you know, the change in body types, the shape he’s gotten [in over] the course of 12, 14 months was unbelievable. I, personally, think he’s failed it [the PED test]. But in some sort of way I hope he hasn’t because it ruins his legacy, and he’s a very, very good fighter.”

Smith recognizes that there’s too much money at stake in Alvarez’s upcoming middleweight championship rematch against Gennady Golovkin for Golovkin (37-0-1, 33 KOs) to walk away from an eight-figure payday over Alvarez’s transgression. He’s still disappointed by Alvarez’s involvement in this PED ordeal and doesn’t believe his excuse.

“For such a high-caliber athlete,” Smith said, “for such a high-caliber sports figure, who’s from Mexico, he knows, he’s seen other fighters, he’s probably seen athletes in other sports fail due to this so-called meat. And I just think he’s that big, and that much in the spotlight, he wouldn’t put himself in that position. That’s what I think.”

Smith, meanwhile, is preparing for his mandatory shot at new WBO 154-pound champion Sadam Ali (26-1, 14 KOs). Their fight hasn’t been officially announced, but HBO is expected to televise it live as part of a May 12 telecast that’ll also include a replay of the Alvarez-Golovkin rematch, scheduled for May 5 at T-Mobile Arena in Las Vegas.

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