Male athletes who had gender reassignment surgery have an unfair advantage over their competitors who were born female, a former National Football League star said.

Retired Green Bay Packers quarterback Brett Favre strongly criticized transgender athletes for having an “unfair” advantage over biological women.

Favre believes weightlifter Laurel Hubbard and other biological males “competing as a woman,” should be banned from the Olympic Games altogether.

“That is unfair,” he said in his “Bolling with Favre” podcast show. “If I was a true female–I cannot believe I am saying that–and I was competing in weightlifting and lost to this person, I would be beside myself.”

These remarks came after the International Olympic Committee (IOC) amended its rules to allow transgender athletes to become qualified to compete. People born male can participate, if their blood testosterone levels measure lower than 10 nanoholders per liter at least 12 months before competing. Sex reassignment surgery is not compulsory, according to the Washington Examiner.

Favre revealed he has no qualms with the transgender movement as a whole, and simply believes that community group should be barred from competing at an Olympic level.

“It is not fair for a man, even if this person wants to be a woman or feels compelled, if you want to become the opposite sex that is fine–I got no problem with it,” he said according to the publication. “But you cannot compete agains males—cannot compete against females.”

Hubbard was already a successful junior weightlifter in the male 105-kg weightlifting class prior to having gender reassignment. Australian Weightlifting Federation CEO Michael Keelan once described Hubbard’s advantages as transcending both physical and psychological levels.

“If you have been a male and you have lifted certain weights, and then you suddenly transition to a female, then psychologically you know you have lifted those weights before,” Keelan said according to Yahoo News. “I personally do not think it is a level playing field. That is my personal view, and I think it is shared by a lot of people in the sporting world.”

Favre also wants the IOC to exclude transgender BMX rider Chelsea Wolfe, who was picked as an alternative for Team USA. He pointed to an old social media post in which Wolfe claimed she wanted to compete for a chance to burn the U.S. flag on the medal podium.

He suggested Wolfe was welcome to compete for “someone else,” just not the United States at the 2020 Summer Olympics.

“To say that is such a slap in our country’s face. I cannot believe this person can be allowed to participate for our country,” he said.