The ringing telephone roused Kerry Vera from a deep sleep. She was in her California home alone when her husband, UFC light heavyweight Brandon Vera, called. Something was up, she knew fairly quickly, for him to be calling so early. It was the middle of the night where she was and she knew he knew that.

But it was when she heard him speak that she knew something wasn't quite right.

"When he called, he was very calm and very quiet," she said. "He was like, 'Um, I just need to tell you what just happened and I need you to fly out here to be with me.' It was weird. It was really weird."

It got weirder when Brandon told Kerry what had just occurred. He'd been sleeping in the Maryland home of his coach, Lloyd Irvin, when he was awakened at 4:20 a.m. Someone was behind him and had stuck a gun to the back of his head.

It was a home invasion. Thanks to Irvin's martial arts training, bravery and quick thinking, Irvin disarmed one of the two men and the criminals raced out of the home. Later, when one of the men was arrested, it was discovered that he had been wanted for five murders.

As a professional fighter, Vera had always felt secure and in control. Suddenly, he realized how vulnerable he was and felt he'd made a mistake not being prepared for the possibility that a criminal with a weapon may invade his home in the middle of the night.

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The events of Oct. 4, 2008, ended rather quickly, but the effects lasted far longer. Vera was suddenly no longer so committed to being the best fighter he could be. The little things which at the highest level of sport make the difference between winning and losing became just that to him, little things. He didn't care enough.

"Definitely, I would definitely, 100,000 percent, agree that security became my biggest priority, the most important thing to me," said Vera, who Saturday at Staples Center in Los Angeles will face former champion Mauricio "Shogun" Rua in the main event of UFC on Fox 4 with a potential title shot at stake.

"I fought, but it was security that I really was concerned about. I started training my dog. I was just determined never to be caught out there slipping again, man. That was a really [expletive] feeling, man, to have somebody throw a gun at the back of your head when you're sleeping at 4:20 in the morning. I found out later they were mass murderers. I could have not been here, you know?"

That realization deeply changed Vera. He didn't have the same passion to learn, to improve, as he once had. Training was something that got in the way of his need to find a way to be as secure as he could be.

He was obsessed and it wasn't with pursuing a UFC title. He nearly tossed aside his fight career to take up the kind of training that Navy Seal Team 6 and Delta Force do. He wanted to become a Tier One operator, the highest level of elite military training.

"I wanted to go through all of the training and learn how to become a Tier One operator so that [expletive] would never happen again," Vera said.

"I was training with certain teams, with certain special forces guys. I went to North Carolina and got to train with some of those guys at the American Training Center. … That was more important to me than fighting at the time."

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