Manly hooker Api Koroisau.

Apisai Koroisau's return from a seemingly innocuous foot issue which ended up sidelining him for 280 days looms as a huge positive amid the gloom of Manly's horror pre-season injury run.

The Sea Eagles will travel to Leichhardt for a round-one clash against Wests Tigers without Tom Trbojevic (hamstring), Dylan Walker (stood down) and big men Taniela Paseka and Kelepi Tanginoa (both knee injuries) as Manly's casualty ward fills up before a ball has even been kicked.

Koroisau at least is set to finally return to the paddock in Des Hasler's first game back in charge at Brookvale, despite not playing in either of the club's trial matches.

The livewire No.9 hasn't been sighted since June when a foot injury he "didn't take too seriously" ended his night early against the Warriors in Christchurch.

What was then diagnosed as a 10-week lay-off was revised to a full eight-month Lisfranc injury – where Koroisau's right foot was crushed to the point where metatarsal bones were displaced from the top of his foot.

Koroisau didn't have screws removed from his ankle until November while stitches remained as Christmas approached, having initially 'jumped around on' the same leg in Christchurch last winter.

"I think the original diagnosis was probably 10 weeks that we put out there," Koroisau said.

Sea Eagles hooker Manase Fainu.
Sea Eagles hooker Manase Fainu. ©Nathan Hopkins/NRL Photos

"We legitimately thought it was maybe a little bone fracture or something of that sort.

"The scans revealed the Lisfranc which was a six-month injury. I was jumping around after the game on crutches and mucking around a little bit. I didn't take it too seriously.

"It was completely gone [at that point]. I think I tried to get back onto the field after I came off. But nothing was working.

"It's feeling really good though so I'm on track for round one".

NRL journeyman Brendan Elliott is expected to take Trbojevic's spot at the back against the Tigers, while unheralded flyers Tevita Funa and Reuben Garrick are in line to replace Walker.

The club is still in talks with the NRL about possible salary cap relief for Walker – stood down under the game's new 'no-fault policy' until domestic violence charges are finalised in court – but may choose not to apply for the discretionary funds.

Meanwhile, Koroisau's absence paved the way for young gun Manase Fainu to emerge. Fainu jagged nine games after an NRL wrangle over his elevation to Manly's top squad.

Koroisau will likely be in line for an 80-minute stint against the Tigers with Fainu serving the last game of a three-match ban from last season, when he pleaded guilty to filming an intimate act without consent.

Tonga's two end of season Tests which Fainu missed have already counted towards the 20-year-old's suspension.

His 95-kilo frame and physicality has him well-placed to fill the utility role this year, with veteran Trent Hodkinson and ex-Titan Kane Elgey also in contention.

"Manase's an incredible player. Definitely if he was at another club he'd be their starting hooker," Koroisau said.

"Right now he's biting at my heels and I'm going to have to be real careful of Manase and I'm really excited to see how he goes this year.

"We're really good friends and I love teaching him and I'm still learning things off him as well. It's a good partnership to have.

"I think he's a good chance of being that No.14 player. He's capable of playing a whole lot of positions and he's quite big so I wouldn't be surprised if Dessie has him in that 14. He'll be a massive asset to the team."