WIOTA, Wis. -

A guy like Adrian Serrano is used to hard hits.

But when he heard the news, and when he saw his student’s name connected with killings, it rocked Serrano harder than any take-down.

“My first reaction was the name had to be wrong,” Serrano said. “Somebody messed up the name.”

Jaren Kuester, 31, was arrested Sunday in connection with a triple homicide in Lafayette County. Three people – Gary Thoreson, 70, Chloe Thoreson, 66, and Dean Thoreson, 76 – were found dead in a home on Philippine Drive in the town of Wiota. After two days of being blocked off, the road is no longer closed. Lafayette County Sheriff Scott Pedley met with the victims’ family Tuesday.

Waukesha police took Kuester into custody Sunday night. He is being held at the Lafayette County Jail on three tentative charges of first-degree intentional homicide.

Serrano has trained Jaren Kuester to reach his life goal. Serrano said Kuester wanted nothing more than to be a professional mixed martial arts fighter. No surprise, Serrano said, because the Kuester clan is filled with natural wrestlers. Serrano trained Jaren’s brother, Jacob, to a championship level.

“They're just from a good family in Waukesha. All five brothers wrestled, and I think all five of them dabbled in this sport a little bit, his brother Jacob the most,” Serrano said.

Serrano never knew Kuester to be violent outside of the ring. He said he kept careful track of his diet, worked out intensely, and didn’t seem to have issues with drugs or alcohol.

“Jaren was a good guy, working hard to make a living, working hard at the gym to get to the point to be a professional MMA fighter, and never knew him to be in any trouble.

Kuester was booked in the Waukesha County Jail on Thursday before the three victims were found dead. According to jail records, there was a warrant out for his arrest for resisting and obstructing and officer. Kuester paid a $303 bail and jail officials let him go.

The connection between the suspect and the three family members found dead in Lafayette County is still unclear. Investigators say the victims didn’t know their alleged assailant. Serrano didn’t know of any connection between Kuester and that area. He considered that one of the biggest mysteries of this case.

“The most bizarre thing is what happened way out there in southwest Wisconsin? I never heard him talk about, he's a Waukesha and Milwaukee guy,” Serrano said. “I never heard of him talk about going anywhere. So just the fact that this incident happened so far away is probably more shocking than anything else.”

Serrano has been in touch with Jaren’s brother, Jacob Kuester, since the arrest was made. However, Serrano said it was only a short exchange offering his support to the family.

“Whatever happened that day doesn't change the way I feel about him. He was always a good guy in the gym, and hopefully this is a mistake, and he'll be back in the gym next week,” Serrano said.