Some like the creative genius of halves, some prefer big props with an offload, or centres and fullbacks with a fend.
And then in that pursuit of NRL finals success, Origin or Test wins, is someone like Damien Cook – your humble hooker.
"You can put a case forward to argue that they are all vitally important," premiership-winning No.9 Michael Ennis told NRL.com.
"And no doubt I'm a little biased but the dummy-half touches the ball more than any other player on the field.
"The decision making in those split moments – as to who needs the ball the most at those critical times – comes down to your No.9.
"So he has to make the choice of which voice he's more comfortable with at that particular moment, or in other words who sounds more confident.
"Then there's what the hooker sees with his own eyes and how to react.
"The way Damien's game has evolved allows him to continue to get better and better at these kinds of moments and decisions."
Another premiership-winning No.9 in Danny Buderus knows only too well the value of halves, props and fullbacks. But the hooker is the oil in those machines.
Cook turns on the speed
"Combinations win grand finals… but they centre on the hooker," Buderus told NRL.com.
"So combinations between your front rowers and hooker; your halves and hooker; and your fullback and hooker. And you need those guys to play really well to make the hooker as effective as he can be."
Effective is Cook's middle name. But he's adding a few others – elusive, entertaining – as he backs up his maiden representative season in 2018 with more hard work in 2019.
"He's endurance is incredible. Once you've experienced the heights of our game, you get a lot of emotions coming as well," Buderus said.
"You've got to keep all that in check to come out the other side – Damien has done that. He's come back to the NRL and seen things a lot differently… a lot more opportunity.
"That means how he can evolve that hooking position using his best trademark, his speed."
Ennis remembers observing Cook when the pair were both at the Bulldogs.
"Having been involved with Damien at Canterbury and seeing his work ethic and how humble he is I knew he must have gone away at the end of last season and worked really hard on his game," he said.
"Explosiveness is his greatest asset because he's got speed we've never seen from a dummy-half before. But there's a lot more to the art of dummy-half than just taking off if there's a bloke on the ground, or when the markers aren’t there.
"[Cameron] Smith and [Josh] Hodgson have those subtleties too which makes them so crafty when there's nothing on," Ennis said.
"And that's where Damien has improved so much this year inside the attacking 20. His pass has improved, his short kicking game has improved, and his genera feel for the opposition defensively has greatly improved."
Damien Cook joins Inside The NRL
South Sydney may have lost their qualifying final against the Roosters but Buderus said Cook's presence means the Rabbitohs are not down for the count.
"He is the one you've got to try and contain if you want to beat Souths. He always puts teams on red alert," he said.
"Damien knows he has speed but he's thinking 'What else can I do to help the team?' That's where he's trying to be more deceptive, and he's improved his kicking and passing as well this year."
And after the NRL finals series fades away, there are Test matches against the Kiwis and Tongans for Cook – the incumbent Australia No.9 – to get his teeth into.
And just like Queensland and Storm have built their squads around Smith, Cook is firming as the central cog in Brad Fittler's NSW side.
"The decision makers for NSW (spine of 1, 6, 7 and 9) have the potential to stay together for the next five to 10 years. That's where Queensland was blessed," Ennis said.
Buderus added: "Once again it's about combinations and building a team around those combinations.
"Damien is central to that – having a halfback that knows his game; a fullback and forwards that really work well with him.
"We saw that with the success of Storm and Queensland."