Sydney Roosters supporters are furious with the NRL for taking away the club's home-ground advantage and scheduling their final against Manly as part of a historic double-header.

Fans are angry about having to share Allianz Stadium with Cronulla, Manly and North Queensland or Newcastle supporters, and believe they have been deprived of what would have been overwhelming home-ground support.

Roosters chief operating officer Ted Helliar, who said the club was given no say in the NRL's decision, understands why supporters are not happy about sharing Allianz Stadium.

''I do understand the frustration,'' he said. ''You echo the sentiment of some of the comments I've seen on social media this weekend.

''We've averaged 20,000 crowd this year. We're the minor premiers yet we still have to share the stadium with three other teams. I do get it but I also understand the commerciality around it as well.

''Our fans are naturally not all that happy about the double-header. They obviously would like to own the stadium and sit in their regular seats and have the Chookpen where the Chookpen usually is. Our fans are feeling like we've lost a bit of home-ground advantage out of it.'' A

double-header could have easily been avoided if the Sydney Swans had played their home final at ANZ Stadium on Friday rather than Saturday, which would have allowed the minor premiers to host their final on Friday night.

However it is understood an agreement between ANZ Stadium and the AFL gave priority to the Swans, forcing the NRL to schedule a finals double-header for the first time.

A stand-alone final against Manly would have meant the Roosters would have had an estimated 60 per cent of the supporter base at Allianz Stadium on Saturday night. That could be halved if Cronulla and North Queensland supporters stay to watch the second game of the double header.

''You have to consider that we might have three sets of supporters against us,'' Helliar said. ''If Cronulla get 14,000 or 15,000 for the first game and they all turn against us, that's not ideal either.''

The Roosters believe they would have been able to attract 25,000 fans on their own if they had a stand-alone final, which would have given them a huge advantage over the Sea Eagles, who in the past two years have managed home finals crowds of 16,678 and 13,972 at Allianz Stadium.

''We've averaged 20,000 this year and we're third in the NRL for crowds,'' Helliar said. ''In round one we had 36,000, on Anzac Day we had 40,000 and then Sonny Bill's game against the Dogs we had 25,000. We also had 19,000 against Melbourne on a Saturday night.

''They've come out in force this year and … I would have thought we would have at least been able to jag 25,000 of our own supporters for a final.''

The NRL has allocated one bay for all four clubs at each corner of Allianz Stadium on Saturday. However, the Roosters are working closely with the NRL to ensure there is a sea of red, blue and white.

''We'll work with the NRL to make sure that as our bay sells out, it will grow. Our message to our supporters is that if you want to own the stadium, buy tickets,'' Helliar said. ''If they sell it out, fantastic. But if they don't sell it out and our fans don't get the best possible outcome for themselves, then it's disappointing.''

Feathers fly in the Chookpen  Roosters fans' online fury

kurtsherlock6: ''Thats bullshit ... We finished 1st & deserve our own home semi. Hope the club fights this.''

Hawkeye:  ''Absolutely totally fricking ridiculous !! ...  let the Sharks play their home semi at their home ground. It will be against an out-of-town team anyway so its not like there will be lots of supporters missing out on tickets. If the  NRL want to play a double-header, do it on sunday at the ground big enough to accommodate 4 sets of supporters.''

Planetboy:  ''It totally dilutes our home ground advantage that we earned for coming first. The atmosphere is going to be crap. Once the first game is finished a lot of the fans will leave. And a lot of the supporters of the teams playing second aren't going to turn [up] at 4pm.''

KnowingNothing: ''What will happen to the Chookpen now? Instead of having seats in the middle, they'll probably chuck them in the corner somewhere. Great home ground advantage for the minor premiers ...''