After a lukewarm start to 2023, the Titans fired Justin Holbrook with immediate effect on Thursday and announced dual premiership-winning coach Hasler would take charge from next season.
Current Titans assistant Jim Lenihan has been appointed coach on an interim basis for the remainder of 2023.
The Titans informed Holbrook and the playing group of their decision on Thursday morning as the culmination of a review into the football program that began last year.
"We think we've got large chunks of that program right," Titans chief executive Steve Mitchell said.
"The piece that we don't know that we've got right at the moment is how the playing group is being brought forward.
"We think we need a winner in place and someone who's got the IP and has been to grand finals.
"It's very unusual to have a coach of Des' ilk in the market where he's literally not employed. Sometimes timing is everything."
Across tenures with Manly and Canterbury since 2004, 62-year-old Hasler has coached in five grand finals, winning the 2008 and 2011 deciders with the Sea Eagles.
The acquisition is a major boost for the Titans, who have played finals only twice in the past 10 years and have never had an NRL premiership-winning coach.
Hasler's sides have become known for their defensive grit, an area where the Titans have struggled under Holbrook.
Hasler's appointment comes after he pulled out of the race to coach St George Illawarra when the beleaguered joint-venture club was on the lookout for a new coach earlier this season.
"I'm looking forward to joining the Titans and to the 2024 season," Hasler said.
"The club has a strong playing roster, the region is blessed with emerging talent and the organisation is firmly embedded in the community."
Hasler's signing comes as star halfback Hunt agitates for a release from the remainder of his St George-Illawarra contract and sets his sights on a move home to Queensland.
The Dragons formally declined Hunt's request last Sunday but he is set to meet with club powerbrokers now his State of Origin duties are over for the time being.
Hunt looms as potential perfect fit for the Titans, who have a superstar-in-the-making at fullback in Jayden Campbell, a dynamic forward pack and a willing halves co-pilot in AJ Brimson.
But Mitchell said the club could not make contact with Hunt until he secured a release from the Dragons.
"We can't talk to Ben about his current contract nor should we, nor will we," he said.
"He hasn't had a call from the club ... He hasn't called anyone at my club."
Holbrook arrived at the Titans after a dominant three years with English outfit St Helens but finished his 82 games with only a 38 per cent winning record.
He lifted the Titans from last place in 2019 to ninth in his first year in charge and locked up eighth place the season after, albeit with a losing record.
The ninth-placed Titans have a 6-7 record this year and have been inconsistent, also developing a bad reputation for coughing up double-digit leads.
Mitchell said Holbrook had taken the news of his axing to heart and he expected the playing group would do the same.
"He's very sad," Mitchell said.
"(The players) are sad and that makes sense.
"They'll miss Justin. I think he's a friend and he's got strong relationships there. But we're about performance.
"We've got a playing group who genuinely want to win. I think they'll want to bring a premiership to the Gold Coast."
