The Storm had taken the lead in the first half through debutant Ben Hampton, who shone at fullback in place of his fellow north Queensland product Slater, before Titans winger Kevin Gordon levelled the scores.
The visitors refused to go away however with Hampton scoring his second midway through the second half following a break down the right-hand side by Will Chambers.
A Luke O'Dwyer try in the dying minutes secured the points for the Titans however and moves the home team up to fifth on the ladder.
Idris was superb for the Titans with 28 tackles, including one big hit on Hampton in the first half, while Queensland Origin outcast Ashley Harrison put in a top display with 33 tackles and 15 hit-ups and hooker Matt Srama posted 40 tackles.
Hampton was outstanding on debut for the Storm, running for 129 metres, while stand-in Melbourne captain Ryan Hinchcliffe posted a game-high 43 tackles.
The Titans had an injury concern of their own with Brad Takairangi coming off in the second half with a rib complaint.
Storm coach Craig Bellamy confirmed Widdop had dislocated his right hip and said the versatile back had been in a significant amount of pain before being taken by ambulance to the nearby Robina Hospital.
"Hopefully it's a clean dislocation, there's no fractures,'' Bellamy said.
"Dependent on that will be how long he's going to take.
"He's in a lot of pain and the boys are really feeling for him at the moment.''
Titans coach John Cartwright was relieved to come away with the win after a first half where his team could only complete 11 of 20 sets.
"I thought it would be pretty tough,'' Cartwright said.
"I knew they'd come here and work on spoiling and trying to grind a win out but that was the pleasing thing, we weathered that and found a way to score points.''
- AAP
