Just like the human body, the spine is crucial to any rugby league team's wellbeing. If your fullback, five-eighth, halfback and hooker are fit and firing, then your side is more than likely on track to challenge for a title. But if just one piece of the prized quartet is removed, then you may as well start planning for next year.
According to the writers at NRL.com, these are the top five spines heading into 2017.
Spine: Greg Inglis, Cody Walker, Adam Reynolds, Robbie Farah/Damien Cook
One of the biggest problems for South Sydney in 2016 was keeping their spine intact for more than two weeks. Halfback Adam Reynolds was plagued by injuries throughout the year and only managed 16 games, Greg Inglis's knees were an ongoing issue, and the chopping and changing at dummy-half made it hard for the Rabbitohs to establish any continuity around the ruck. That should all change next season with the acquisition of veteran Blues No.9 Robbie Farah. The former Wests Tigers rake injured his biceps in pre-season training but the club says he will be fine for the Round 1 clash against his former team. With competition from explosive hooker Damien Cook, Farah isn't guaranteed a spot - expect both hookers to be aiming up to secure the number nine spot. 'Rookie' Cody Walker will have taken a lot out of his first year in the NRL and will provide the perfect attacking foil for Reynolds's controlled game.
Spine: Darius Boyd, Anthony Milford, Ben Hunt, Andrew McCullough
No, this is not the Maroons spine. But it could be in a few years. In isolation, each of these players is highly gifted, but when they come together in unison they are an almost unstoppable force. Cast your minds back to the 2015 preliminary final against the Roosters. The Broncos scored six tries that night; four of those were scored by this quartet. Not a bad effort. The Broncos spine combined for 31 tries and 55 try assists in 2016, and that included a quiet period for their halves in the middle of the season. Anthony Milford is perhaps the most dynamic No.6 running around, Ben Hunt is always a threat when he takes the line on, and McCullough is Mr Reliable at dummy-half. All three plus fullback Darius Boyd are off contract at the end of 2017 and will be priority signings for Wayne Bennett going forward.
Spine: Roger Tuivasa-Sheck, Kieran Foran/Tui Lolohea, Shaun Johnson, Issac Luke
With the entire Kiwis spine at their disposal, the Warriors are well placed to take the competition by storm in 2017. Yet there are so many question marks about how they will perform next year. How will Roger Tuivasa-Sheck go following his knee reconstruction? Will Kieran Foran be cleared to make his return after leaving the Eels on compassionate grounds? Are Shaun Johnson and Issac Luke going to play to their potential every week? If the answer to all of those queries is "yes" then you are looking at a top four side. Foran is the man who can take the pressure off Johnson, and if they click as a halves combination then that only makes RTS and Luke more of a threat.
Spine: Lachlan Coote, Michael Morgan, Johnathan Thurston, Jake Granville
The Cowboys might have lost a couple of key contributors up front, but the 2015 champions have kept their formidable spine intact for the third season in a row and are well placed to launch another premiership assault. In Jake Granville they have unrivalled speed out of dummy-half. Michael Morgan is also pretty quick and provides a bigger body on the edge. What Lachlan Coote lacks in size, he more than makes up for in bravery, and his ball-playing has also come on in leaps and bounds since making the move north. Then there's the man simply known as JT. Time and time again, Johnathan Thurston has delivered in the clutch moments – think the 2015 grand final, last year's epic semi-final against the Broncos or basically any State of Origin game.
Spine: Billy Slater, Cameron Munster, Cooper Cronk, Cameron Smith
Billy Slater, hopefully, after two injury-ravaged seasons, 2017 will be the year the fullback stays on the field long enough to show that he is still the premier custodian in the game. While the 33-year-old recovered from back-to-back season-ending shoulder injuries, youngster Cameron Munster took the reins at the back and made the position his own. Now, with Blake Green at the Sea Eagles, Munster is set to shift to five-eighth where he will be given a licence to thrill while the 'big three' will go back to what they've done best since 2006. With revenge on their minds after last season's grand final defeat, you'd be a brave man to write the Storm off in 2017.