MANILA, Philippines – Former champion Junior “Cigano” Dos Santos of Brazil admitted that he was dealing with some personal issues when he fought Cain Velasquez at UFC 155, which ultimately led to him losing the UFC heavyweight title.

“Really, it was my head. I had some personal things going on and a bit of my attention was lacking because of it,” Dos Santos told Nagradedo MMA. “I was not good with my head.”

“I was having personal problems and I did not do well mentally in the fight,” he added.

Dos Santos became the heavyweight champion when he knocked out Velasquez in just over a minute at UFC on FOX 1 in November 2011. But Velasquez thoroughly dominated the Brazilian in their rematch, eventually winning via unanimous decision.

“Velaquez did his game (plan) very well,” Dos Santos said. “He imposed his tactics, but I did not react. I was there, but mentally, it seemed I was not.”

“I followed him and I just defended myself. I was strong in all my other fights, I was always attacking and going forward, but this time I just walked back and defended myself,” he added.

Dos Santos also revealed that he was suffering from kidney problems during the fight.

“Soon after the fight, I went to the hospital and had a scan, which showed my creatine was too high. The normal level is up to 300, mine was in 1400. I also had trouble in the urine and kidneys,” he said.

Creatine is an amino acid produced in the kidney and liver, which helps supply energy to the muscles.

“The explanation of the doctors is that I pushed over the line, I over-trained,” Dos Santos explained. “Problems could have happened even before the fight.”

The Brazilian said he has learned from his experience.

“Going forward, i will be more careful... I need to know how my body is reacting to what I am doing. We need to a bit more professional about it. I will do tests during preparation,” he said.

“The fight also taught me that I have to be stronger with the head, think about strategy and monitor the tactical part,” Dos Santos added.

He is hoping to get a third fight against Velasquez soon.

“I won the first, he did a good job in the second. I think the third fight has to happen,” he said.