Keith Titmuss suffered a seizure after a cardio workout at the club’s base at Narrabeen, on Sydney’s northern beaches, on November 23, 2020.

He died five hours later in hospital.

After giving evidence at an inquest into his death, Hasler addressed Titmuss’s family, including father Paul and mother Lafo, directly.

“Keith was a beautiful boy, he was much loved and very highly regarded and respected,” the premiership-winning coach said.

“I’m just so heartbroken of the events that transpired.

“I remember talking to Paul and Lafo, and Lafo saying that morning they had breakfast together and (Keith) walked out the front door, but that evening he never came home.

“I am so, so sorry and I share your heartbreak, I really do.”

An inquest into the 20-year-old’s death previously heard he most likely suffered exertional heat stroke, although an autopsy was unable to confirm the exact cause.

Hasler, now head coach of the Gold Coast Titans after his 2022 sacking from the Sea Eagles, said young players in particular were often eager to prove themselves.

But it was up to the club to create a culture that made it acceptable not to overexert themselves and cause an injury.

“It’s really important once (players) come under our duty that there is a real focus on knowledge absorption and understanding about their journey,” he said.

“From the outset, particularly for younger players, there is a need not to overstride … to overcome that emotion of, ‘I must succeed, I must impress the coach’.”

Asked if he would have conducted the training session differently, knowing what he did now about heat exertion, Hasler said it was a difficult question to answer in hindsight.

“Anyone that is under my care, I would do anything to prevent such a tragic accident,” he said.

“Before the training sessions start we instruct the players and show them the plan of what is to happen and if they’re feeling ill or feeling like they’re not coping well with it … that they raise their hand and let us know.

“It’s essential (for them) to understand the last thing we want to do is to injure them or not to have them on the field, that’s really important as part of our culture.”

Hasler said the session would have been challenging as a training session following the off-season break.

But there were also rest breaks so that players could recover and rehydrate in between cardio phases, he added.

The inquest previously heard one player describe the session as a “nine out of 10” for intensity.

But Hasler said he would rate the intensity as between six and seven out of 10.

“It was the first training session back with the new group so we were very cautious of not overloading,” he said.

“This is new to them, it makes no sense to get a player to go beyond what they can because we want to keep them on the field, keep them training and get them to the stage where they can compete.”