Tom Loeffler, promoter for IBO, WBA, WBC middleweight champion Gennady Golovkin (38-0-1, 34 KOs), says his fighter is still harboring some very angry feelings over Canelo Alvarez's drug tests.

Golovkin's anger began in March, when it was revealed that Canelo failed a pair of drug tests in February. He came up positive for the banned substance clenbuterol.

The drug testing issue was the main factor in forcing their originally rematch date of May 5th to fall apart.

They are now scheduled to collide on September 15th, at the T-Mobile Arena in Las Vegas.

Canelo has maintained from the start, that his positive tests were caused by his inadvertent ingestion of contaminated meat while training in Mexico.

But Golovkin is not buying that excuse and accussed Canelo of being a user of performance enhancing drugs.

“Triple G feels that when you’re at that level, you should be held to a higher standard,” Loeffler said to the Press Enterprise. “Regardless of how a substance got into your body, you need to know what you’re eating.

“And athletes at that level can afford to have the type of training camps or the type of food preparation where you don’t take that type of a chance of not knowing what gets in your body.”

If the shoe was on the other foot, Golovkin believes the critics would have roasted him.

Canelo has taken a lot of heat for the positive tests and his credibility has been damaged - but Loeffler believes this rematch can undo the damage of that controversy.

“I know Triple G was extremely disappointed and frustrated with the positive tests,” Loeffler said. “As I’ve said before, had Triple G tested positive, everybody would have jumped on him.

“And so I think Canelo took a big hit and this is the fight that can rehabilitate his image.”