Des Hasler says Manly "were dudded" by the critical sin-binning of star forward Jake Trbojevic against South Sydney but the NRL has already moved to declare the clutch call as the correct one.

Trbojevic was given 10 minutes in the bin with the Sea Eagles holding a 26-20 lead and the ascendancy when he made contact with Dane Gagai as he pushed up in support of a Rabbitohs break.

Souths rattled in two game-winning tries while Trbojevic cooled his heels, the 34-26 win ending Manly's giant-killing season in cruel circumstances.

Hasler was emphatic when asked if the Sea Eagles would have held on for the win had Trbojevic not been marched.

"Of course we do, you know that. You don't have to ask me that," Hasler said.

"Do I think we were dudded? Yep. I think we were dudded."

Hasler had moments earlier been filmed on the phone having a heated discussion NRL Head of Football Graham Annesley as he paced the dressing room after full-time.

Annesley issued a statement in the wake of Hasler's comments, pointing to two incidents last week where Canberra's Elliott Whitehead and Jarrod Croker weren't sin-binned for what he deemed professional fouls against Melbourne.

"It was a professional foul in a try-scoring situation," Annesley said.

"Last week I publicly criticised a referee for not using the sin-bin in similar circumstances. If Jake doesn't grab the support player, the consequences don't occur."

Hasler was adamant Trbojevic's offence was worthy of a penalty at most, but had no issues with Brad Parker's earlier sin-binning for tripping James Roberts as the Bunnies centre pursued a grubber.

"I can wear the first sin bin," Hasler said.

"But I thought the call on Jake in the second half was a bit tough.

"Was it a penalty? I don't mind a penalty.

"I can handle a penalty. Did he deserve to get sent off? No, no I didn't think he deserved to get sent off.

"I don't want to detract from what I thought was a pretty good game of footy.

"Plenty of points, plenty of tries, plenty of tension. I don't want to detract from the way both sides play and the way Souths won the game.

"You just don't want to see the game coming down to crucial calls like that. I spoke to Graham Annesley straight after the game and I said to Graham 'that's not right'."

Trbojevic cut a dejected figure in the Manly sheds after the game and declined requests for comment.

"It hurts hey, it hurts so much losing like that," Trbojevic told Channel Nine in an on-field interview after full-time.

"That hurt a lot, sitting in there watching your team-mates, it was hard mate, it was hard.

"It probably cost us the game in the end, they scored two tries while I was off and it hurts."