John Ruiz credits the fiery temperament of his mother for giving him the “anger” needed to regain his WBA world heavyweight title.
Victory over David Haye in Manchester on Saturday night would see Ruiz join all-time greats Muhammad Ali and Evander Holyfield in seizing the crown for a third time.
The 38-year-old is a heavy underdog against an opponent who is nine years his junior, yet remains quietly determined to condemn Haye to the briefest possible reign as heavyweight champion.
A former Catholic altar boy of Puerto-Rican descent, Ruiz was kept on the right side of the tracks during an impoverished childhood by his ferocious mum Gladys.
The spirit she displayed in battling alone to provide for Ruiz and his three brothers continues to inspire the American as he enters the twilight of his career.
“I do enjoy fighting, maybe it's the anger inside of me,” he said yesteray after his media workout at the Northside Amateur Boxing Club. “I'm looking forward to moving on and being with my family because I have a three-year-old who I want to spend a lot more time with.
“But I still have a little fire in me for the sport so I want to go out there and do the best I can.
“Anger has been part of my life. There's stuff that's happened in my life that has made me angry, but I control it.
“I do this for my kids, to make sure their future is better than mine was. Come fight time that's all that's all I think about.
“I get it from my mother, my mother loves to fight. My mum has a hot temper — if you get in her face she'll get back in yours no matter who you are.
“I think my brothers all got it from her as well. She raised us on her own and did the best she could.
“She kept fighting to make sure we went to school and better our lives. She made sure we stayed on the right path.
“She worked at a fish market and did all sorts of jobs to look after us. I look back and thank her for what she did for me.
“She gave us pride in being from Puerto Rico and made sure we kept our heritage, but at the same time made sure we prospered in our lives.”
Known as the ‘Quietman', Ruiz is a different personality to Haye, who is fast becoming a master of self-promotion.
They do share common ground, however, with the name of Nikolai Valuev appearing on both fighters' records.
Haye won a majority points decision against the lumbering Russian giant in Nuremberg last November to seize the WBA belt that will be on the line at the MEN Arena on Saturday night.
Ruiz fared less well, dropping controversial decisions in 2005 and 2008 that still rankle with Haye's victory — disputed by some following a dreadful spectacle — enhancing the feeling of injustice.
“I was surprised David got a decision. I tried three times to get a decision fighting in Germany and felt like I won them all,” said Ruiz. “They all went against me, but sometimes luck does play a part in this game.
“When you get cheated that way, you want to get back there and prove people wrong.”