Manly five-eighth Kieran Foran battled through serious injury to take the field against St George Illawarra in Sunday's NRL final, but he won't get a chance to do the same for New Zealand in the Four Nations tournament at season's end.

Foran suffered a grade three tear to the AC joint in his left shoulder in last week's loss to Canterbury, but with the help of a needle pre-game and at halftime, he bravely soldiered on in his team's 28-0 loss to the Dragons at Kogarah.

The Kiwis' Four Nations campaign has taken a huge blow with Foran to undergo surgery this week which will rule him out, and captain Benji Marshall (knee) and powerhouse forward Frank Pritchard (hamstring) sure to be in doubt after also suffering injuries in the opening weekend of the playoffs.

Foran revealed what he went through just to play against the Dragons and said he is devastated to miss New Zealand's battles with Australia, England and Papua New Guinea in late October.

"It's pretty messy in there. I did a fitness test on Friday, so I tested it all out on Friday with a needle and it worked out alright so they gave me the thumbs up.

"I probably wouldn't have pushed it if it was different circumstances but as you can see we were down so many troops through suspensions and injuries and what not, I just thought if I could needle up and get through it I wanted to be out there and help the boys out." Despite playing Sunday's match badly injured, Foran confirmed there was little risk of making the situation worse and said he had already spoken to Kiwi coach Stephen Kearney last week to notify him of the bad news.

"I've got to go see the surgeon (on Monday) and hopefully they operate at some stage this week," he said.

"I've spoken to him (Kearney) a few times this week and I've pretty much stated I'll be unavailable. I'm going to have to have a clean out and fix the whole AC joint up so I don't think I'll be available.

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