Canelo Alvarez and Gennady Golovkin
Canelo Alvarez and Gennady Golovkin will finally meet in the ring again on Sept. 15. In this picture, Alvarez (L) and Golovkin face off during a news conference at Microsoft Theater at L.A. Live in Los Angeles, Feb. 27, 2018, to announce their upcoming rematch. Kevork Djansezian/Getty Images

Canelo Alvarez believes Gennady Golovkin is repeatedly bringing up his failed drug tests as an excuse for when the latter loses in their September rematch.

Both fighters put up a boxing clinic in their middleweight title showdown in September last year; however, the night was marred by the scorecards of the judges, eventually deeming the contest a split-decision draw despite many favoring Golovkin as the winner.

The rematch was set to take place in May this year but it was soon called off after Alvarez's multiple failed drug tests for clenbuterol in February saw him receive a six-month suspension from the Nevada State Athletic Commission — with Golovkin notably putting pressure on them to punish him.

Alvarez cited contaminated meat from Mexico as his reason for failing those drug tests, a common occurrence for boxers in the past; however, "GGG" was not buying it as he went on to claim the Mexican was a long-time user of performance enhancing drugs.

After months of negotiations, the rematch is finally confirmed to take place Sept. 15 and because of Golovkin's comments and everything that has transpired since their first fight, things are extremely personal now.

Alvarez claims he lost whatever respect he had for the unbeaten Kazakh and is promising a knockout this time, though he did so before the first fight as well. He also thinks Golovkin and his team are bringing up his failed drug tests as an excuse for when he eventually wins the middleweight titles.

"Look, I think they can talk or can do, say whatever," Alvarez told ESPN Deportes, as per BoxingScene. "I think it's an excuse because he knows he's going to lose Sept. 15 and he wants to take hold of that, I think they should do research because clenbuterol is not a steroid, it's not a steroid and it does not help you, it does not help in performance, not in muscle, far from it, I think they should do some research before speaking.

"... And I think they're making a lot of excuses because he knows he's going to lose on Sept. 15."

Alvarez is not completely correct in what he mentions about clenbuterol. It's a substance traditionally used to treat asthma. However, it is also "regularly given to animals in China and Mexico to increase lean muscle mass and improve the overall livestock production" as per the Metro.

Because of this, it is banned for athletes to use as it can help them lose fat extremely quickly and build lean muscle, which in essence, can improve one's physique and performance.

Regardless, it was Alvarez's first failed drug tests in his professional career and he is expected to be clean for the rematch in Las Vegas. The events that have transpired since his failed tests have seen his odds to win go from +140 to +155.

Golovkin meanwhile, is a slightly bigger favorite as he went from -170 to -190.