Kieran Foran's investment in Manly's most prized asset began well before his storied homecoming, as he and fullback Tom Trbojevic bid to turn research from Australian and US experts into an injury-free 2021 campaign.

Trbojevic's hamstrings rank as the most discussed in rugby league after three tears in the past 18 months, limiting him to just 19 games in two seasons.

Foran knows all too well the frustration and scrutiny that comes with recurring injuries, and got in contact with Trbojevic last pre-season to offer support as he worked his way back from his own shoulder reconstruction at Canterbury.

Once the Sea Eagles swooped on their old premiership-winning half and Foran's return to Manly was sealed, he and Trbojevic were sent on a week's expedition to Melbourne where they both underwent extensive tests on their troublesome hamstrings.

The Australian Catholic University's research on the pair before Christmas was in turn shared with counterparts at the University of Wisconsin, the recipients of a $300,000 NBA grant in recent years for their work around hamstring injury prevention.

Trbojevic and Foran have overhauled their weight and strength programs as a result of the analysis, continuing a rehab road they started down together over a year ago.

Turbo: Foran has an aura

"I didn't have his number and I grabbed it off Cherry (Daly Cherry-Evans) probably 12 months ago as he was going through these injuries," Foran said on Monday.

"I'd flick him a message and just reach out. We were going back and forth over the last 12 months, keeping each other updated, talking about the mental side of what it takes.

"It was interesting, we've jokingly spoken about how tough it is to get these hamstring injuries and come back from them."

Trbojevic came into first grade as a winger during what long looked to be Foran's final year at Manly – the 2015 campaign when his own hamstrings became an issue, limiting him to less than 20 games for the first time in six seasons.

Since leaving the Sea Eagles Foran has played just 66 games from a possible 116.

As he wages his own bid to stay on the paddock, the veteran Kiwi has kept a close eye on Trbojevic, aware of the weight his next comments carry.

"He's as good a player as I've ever played with," Foran said, no small rap considering Cherry-Evans, Roger Tuivasa-Sheck, Jamie Lyon and Brett Stewart count among his teammates over the years.

"I've thought long and hard about it. The growth in his game since I last played with him, in 2015 he'd only just debuted and was playing on the wing.

"I've watched him closely the last few years, I've watched his game grow and been highly impressed. Coming here, training with him in the flesh, I can just see how impressive a footballer he is.

"He's blowing my mind. You can see why he's so vital to this club. As is everyone, everyone plays a role. But every now and then there's special footballers that come along."

Foran: 'Surreal' being back in Sea Eagles nest

For Trbojevic, Foran is "back where he belongs at Manly", and a welcome sounding board during both their trip to Melbourne and training on the northern beaches since.

Captain Cherry-Evans concedes that the sight of Trbojevic pulling up during a sprint drill recently had his own heart in mouth, but the 24-year-old fullback insists he bears no mental scars from the past two seasons.

"I'm alright with it. A lot of people ask that but I know I feel fit," Trbojevic said.

"I can see why you're asking the question but it doesn't affect me too much."

Of the reported hamstring setback a few weeks ago Trbojevic said: "It's just the programs we've been running. I'm always kind of sore but that's the idea of it, there's definitely no real issues.

"The training program idea idea is strong hammies with long fascia lengths to reduce the risk of injury.

"It changes the weights programs mostly and what you do there."

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