The native of Giurgiu, Romania who emigrated in 2003 and was sworn in as a Canadian citizen last week will be the underdog when he faces International Boxing Federation welterweight champion Kell Brook in Sheffield, England on Saturday.
But Dan (34-2) is used to being underestimated.
"I'm motivated and hungry," the 33-year-old from Montreal said. "I want it a lot.
"I don't know how much (Brook) wants it or how seriously he takes me, but I'm 100 per cent focused and I want that title. This fight is life-changing for me, my family, for everyone around me."
His trainer Pierre Bouchard feels Dan can pull off an upset, even if he will be fighting before 10,000-plus hostile fans in Brook's hometown.
"There are not a lot of weaknesses, but by studying him, I think we found some," said Bouchard. "His weaknesses are Jo Jo's strengths; that he doesn't like when you get close to him. He doesn't like the intensity. Jo Jo's got both. It should make it a good match."
Brook (33-0) will make the first defence of the title he won in August with a majority decision over highly regarded Shawn Porter in Carson, Calif. It is a mandatory defence against the IBF's top contender, Dan.
It is also the 28-year-old Brook's first fight since he was slashed on the left leg by an unknown assailant while on holiday in Tenerife in September. Brook was left with a nasty scar but said he has fully recovered.
Brook insists he is not looking past Dan, a solid technical boxer and a southpaw who once fought 10 rounds with a broken jaw.
But he has spoken openly of the big money bouts that may come with a victory. He hopes to face the winner of the welterweight mega-fight May 2 in Las Vegas between Floyd Mayweather and Manny Pacquiao.
If not that, he'd like a crack at fellow Briton Amir Khan. There are many star welterweights, including Tim Bradley and Juan Manuel Marquez.
"He said 'I don't overlook Jo Jo but I want to get this mandatory out of the way,' " said Dan. "Actually, he is overlooking me, but it doesn't bother me.
"I'm focused 100 per cent on this fight."
Dan is not a knockout boxer, with only 18 KOs, but he has never failed to go the full distance.
And he's used to fighting on the road. His two losses were by split decision to Selcuk Aydin in Turkey. He went twice to Kevin Bizier's home town of Quebec City and earned majority decisions, including his last bout on Dec. 19.
Dan doesn't feel he needs to put Brook on the canvas to get a decision in England.
"My goal is to go there, perform, make an exciting fight and do my best to win," he said. "I don't stress much about the ref, the judges.
"I don't have to knock him out. I'll go there and perform 100 per cent and show the judges I deserve the fight."
Notes: Canada's lone world champion, Adonis Stevenson of Montreal, will defend his WBC light heavyweight belt April 4 in Quebec City against Australian Sakio Bika. . . Montreal light welterweight Dierry Jean was picked as one of Pacquiao's sparring partners, reportedly because he has a similar style to Mayweather.