Greek Australia boxer Michael Katsidis will be fighting for two interim world boxing titles in Las Vegas next Sunday 10 April when he takes on American Robert Guerrero.

But the 30-year-old Queenslander says he is still “coming to terms” with the death of his brother Stathi Katsidis, who was a three-time Brisbane jockeys premiership winner. Stathi was found dead in his Brisbane home on October 19, 2010 from a combination of drugs and alcohol.

“Stathi and I were very close and I guess I’m still coming to terms with his death,” Katsidis told reporters. “Once the Katsidis family has control of Stathi’s affairs, which my lawyer is working on now, I want to know what really happened, so my family and I have some closure.”

Michael Katsidis has the opportunity to take the two titles from Mexico’s WBA Super world lightweight and WBO lightweight world champion Juan Manuel Marquez as he is undecided about his next fight. Both organisations have deemed the winner between Katsidis and Guerrero will be declared their interim champion. Katsidis was unable to beat Marquez in November last year, when Marquez claimed the win after 9 rounds.

But Katsidis is under no illusions fighting for the dual titles with Guerrero, (28-1-1, 18 KOs) a former IBF featherweight and super featherweight world champion “Two world titles and at the end of this whole thing I think it’s going to be very happy days, I really do,” Katsidis said. “I think I’ve got it in me and I’ll give it my all, 100 per cent.

“It’s going to be the toughest fight of my life, this fight,” Katsidis said. “I’m going to have to pull out everything and more to win this fight.”