A video has emerged from a transgender hockey tournament held last month, revealing a transgender man suffering a concussion after being pushed into the boards by a transgender woman.

I know that sentence may sound confusing, so let’s use biological terms: a man gave a woman a concussion.

The Team Trans Ice Hockey Draft held in Middleton, Wisconsin took place last month and was the first tournament to be comprised of exclusively trans athletes. About 80 athletes participated, some identifying as male and some identifying as female. The tournament gained the attention and support of the NHL.

Naturally, the NHL turned the replies off of their Tweet after expressing their support of the transgender tournament. The NHL couldn’t help itself from making the same mistake all the sports leagues do: completely forget the values and demographics of their audience.

The video, which has largely been unreported by mainstream media, shows “transgender man” Daniel “Danny” Maki suffering a concussion. While the impact doesn’t look severe, the sheer size difference of the two opponents was enough for Maki to be rushed to the hospital and treated for a concussion.

Allowing men to compete against women in physical contact sports does nothing to “promote equality.” The physical advantages that men have over women in these sports are staggering. From lung capacity, to bone density, to muscle fibers, men have the biological upper hand. Men are stronger than women, and creating an environment where they can dominate the opposite sex achieves nothing for “social justice.”

There has been a lot of debate about what the future of sports leagues should look like with the emergence of transgender athletes. The two solutions that rational people come to are either 1.) only allow athletes to compete with their biological sex, or 2.) create a transgender league. The creation of an all-transgender hockey tournament does a good job of protecting women’s sports. But should we really applaud a sports victory when it involved biological men hurting women?