Jake Paul is giving big-time hater energy after he posted a tweet celebrating former boxing world champion Claressa Shields' defeat and calling her a "loser." The boxer lost to Abigail Montes in her first mixed martial arts match on Oct. 27.  

The trash-talking between Shields and Montes began when Shields questioned if the former YouTube star would be a formidable opponent.

"I don't know what world people live in that they think a man [could beat me] who has not been to the Olympics, who has not fought professionally. There are a lot of women in boxing who could [out-box] men, especially a regular Joe like Jake Paul," Shields said, according to Sky Sports. 

Based on her successful track record, Shields was correct in the evaluation of Paul's athletic prowess, and he did not take the disparagement lightly.  

The situation is particularly disappointing since Shields promotes the sport and cheers on the fighters. No one other than UFC President Dana White and boxer Shakur Stevenson has defended her.

The 26-year-old is one of the most decorated women amateur boxers, was a middleweight world champion and is an Olympic gold medalist, further rendering Paul's attack against Shields invalid. 

"I feel like when Jake Paul was saying that, I don't understand how he could talk," Shakur Stevenson said on SiriusXM's Fight Nation.

"Like he went and talked s**t to her, and it's like she's actually fighting MMA people. Like she fought some people that actually do MMA. Everybody that Jake Paul goes fighting in the boxing ring, he has not fought one real boxer yet. The first fight was against a YouTuber, and the other one was against a wrestler, I think. The next one was against an MMA fighter. He's never fought one real boxer yet, so I don't understand how he even have the right to talk s**t to Claressa Shields."

UFC President Dana White, who has also contended with Paul, chimed in.

"Nothing but respect for Claressa Shields. To be looked at as the best female boxer and to come over here and start training and start to do this, not easy, and nothing but respect for her. She lost a split decision? Which is even more impressive; in her second fight, she loses a split decision, which means one of the judges thought she won the fight," White said, MMA Fighting reports. 

"He better be careful, she might knock him out. So Jake Paul calls Claressa Shields a loser? Claressa Shields is nothing but a winner who actually fought real people in her weight class, in her own age, in her own sport and then goes over to MMA and tries to win a world title. That's not a loser; that's a winner, OK?"