UFC 300 co-main event plunged into controversy as Yan Xiaonan is allowed to fight on after being choked unconscious and using ‘illegal’ substance to recover

Daniel Cormier claims Yan Xiaonan was revived by an ‘illegal’ substance in the UFC 300 co-main event.

Weili Zhang successfully defended her UFC strawweight title via unanimous decision on Sunday morning but the fight was plunged into controversy at the end of the first round.

After being dropped by a well-timed left hook in the opening stanza, Zhang dragged Yan to the mat and locked in a rear-naked choke.

The submission was in tight but Yan refused to tap out as she faded from consciousness.

The referee then pulled both women apart as the buzzer sounded and a groggy Yan stumbled over to her corner.

As she sat down on her stool, water was dumped on her head and then it appeared as though she was given some smelling salts to wake her up.

Daniel Cormier picked up on this from the commentary desk.

He said: “In the corner, the cutman said, ‘I can wake her up’ and then he gave some smelling salts or something.”

Joe Rogan responded: “Oh no, really? Wait a minute, are you allowed to do that?”

Social media was then flooded with fans insisting the substance is ‘illegal’.

One fan wrote: “Only in the UFC would we watch someone get choked out, go out after the horn, get back to their feet, sniff illegal smelling salts, then go and start dominating as if nothing happened.”

Another tweeted: “Yan’s corner used illegal smelling salts in ther corner.”

A third added: “Aren’t smelling salts illegal???”