Mauricio Sulaiman backed the WBC’s decision to give Francis Ngannou a top-10 ranking despite his failure to win either fight in his career so far.
Ngannou, a former UFC heavyweight champion, crossed over into boxing last year, with his first fight against WBC champion Tyson Fury in October.
The MMA star shocked Fury, and the public, when he knocked his opponent to the canvas and only lost via a split decision, with many believing he had done enough for victory.
He followed that up last weekend against Anthony Joshua, with another fight in Saudi Arabia, but suffered a comprehensive second-round knockout defeat.
Joshua now awaits the winner of Fury vs. Oleksandr Usyk, shown live on May 18 on DAZN PPV.
After the Fury fight, the WBC placed Ngannou in the top 10, and ahead of Joshua vs. Ngannou, there were many observers who backed a potential upset.
Speaking to Sky Sports, Sulaiman said: "100 per cent [we stand by the decision to rank him in the top 10], just by facts. Everybody criticised the WBC, myself, the ratings committee.
"They jumped the gun and a month later the fight is announced against Joshua and nobody said anything. It is about tendency, we don't go or rule or make decisions by popularity. It is not a popularity contest.
"We have ranked so many muay thai fighters that convert to international boxing."
He added: "Nobody says anything but then Ngannou is such a big name it becomes a controversy and then comes Joshua and knocks him out in two rounds
"[Joe] Frazier was knocked out in two rounds by [George] Foreman. Does that make Frazier a bad fighter that should have not been the champion after beating Ali?
"Ngannou came close to beating the WBC champion Fury, knocked him down, and it was close to a split decision.
"Joshua looked great, that is why he is the No 1-ranked contender in the WBC and I stand by the ranking of Ngannou.
"We are doing the rankings for this month as we speak and we will see where the committee places Ngannou."
Live on DAZN: Watch William Zepeda vs. Maxi Hughes on March 16