Anton Lienert-Brown's importance to the All Blacks will be evident this year more than any other.
Of all the questions facing the All Blacks selectors as they ponder the intricacies of their squad for the start of the test season next month, midfield is the most problematic.
For starters, JackGoodhue's season-ending ACL injury robs Ian Foster of his preferred pairing.
In last year's condensed campaign, Goodhue started inside Lienert-Brown in four of six tests after Rieko Ioane was given the initial nod at centre while Paris-bound Ngani Laumape had one chance at No 12.
Last year's preferred Goodhue-Lienert-Brown pairing was a role reversal on the combination the All Blacks adopted at the 2019 World Cup, with Leinert-Brown used at second-five and Goodhue playing centre in Japan.
This year's full test calendar would have been a chance for that duo to further develop and cement their status but with Goodhue sidelined, the All Blacks are left to review alternatives – none of which tick every box.
At this point it seems probable, highly likely, even, the All Blacks will start the year by pairing David Havili and Anton Lienert-Brown together.
Havili prefers fullback but Goodhue's absence forced him to fill the second-five breach for the Crusaders this season. On the whole, Havili has shone in that role.
After several years of injury troubles restricting him to the fringe of national fullback considerations, there's a sense of irony Havili will not only push his way into the All Blacks but potentially start in the midfield.
In many ways Havili is a different profile of athlete from the second-five the All Blacks have historically favoured. He certainly doesn't fit the hulking Ma'a Nonu, Sonny Bill Williams mould. What Havili does bring, however, is another natural playmaking and kicking option which will help alleviate pressure on Richie Mo'unga and Beauden Barrett.
Rieko Ioane and Braydon Ennor are the other midfielders expected to be included.
Ioane, though, is yet to convince he is better suited to centre than wing, where he's started 26 of his 33 tests, for the All Blacks. His one start at centre last year against the Wallabies in Wellington didn't go overly well when he dropped the ball over the line and was exposed defensively on one occasion. This season for the Blues he's made plenty of metres but his decision-making and instinctive ability to create and feed his outsides hasn't dramatically improved, leaving the same conundrum of where he should feature for the All Blacks.
Ennor has long been on the All Blacks radar – his pace on the outside break from centre earning him a test debut off the bench against Argentina prior to the 2019 World Cup. Yet has just returned from an ACL injury that usually takes a year to return to peak form. Just ask Damian McKenzie, who two years after his ACL is only now back in a groove.
Elsewhere the All Blacks midfield options are unproven. Quinn Tupaea put his hand up with one standout performance against the Blues in Hamilton earlier this season but is only now returning from injury and therefore light on a body of compelling work. Fellow Chiefs midfielder Alex Nankivell impressed against the Crusaders in Christchurch with his offload that set McKenzie away for a try in the Aotearoa final.
Both prospects remain raw at this stage, though.
Peter Umaga-Jensen made his test debut off the bench against the Wallabies at Eden Park last year and travelled with the squad to Australia. This year, however, following the arrival of his first child, Umaga-Jensen has struggled to start for the Hurricanes with Billy Proctor preferred at centre.
Scott Gregory has flown under the radar at the Highlanders after making the switch from fullback, where he endured a horror Super Rugby debut, to second-five. Gregory offers a powerful presence but would be something of a bolter given his recent transition.
Leicester Fainga'anuku is another outside contender but, at this stage in his career, he is better suited to the wing.
All of which leaves Lienert-Brown standing well above the pack.
With Chiefs captain Brad Weber benched and McKenzie missing through suspension, it's no surprise Lienert-Brown stepped up against the Rebels in Sydney on Sunday, taking it on his shoulders to lead and demonstrate his class.
In the transtasman competition Lienert-Brown has made the most clean breaks (10 alongside Julian Savea and Bryce Heem), beaten the most defenders – (19 with Jona Nareki and Salesi Rayasi) and made the most offloads with 11. He's also scored three tries and sits fourth – the top-ranked Kiwi - with 46 carries to highlight his work-rate.
Those numbers, while impressive, only go so far to underline the dedicated work Lienert-Brown does on the mental side of the game; his superb anticipation, line running and invaluable heady nature.
At 26-years-old and set to notch his 50th test in the first outing of the season against Tonga, he is approaching an age of optimal maturity in the black jersey.
Given the other unproven candidates challenging for this unsettled area, Lienert-Brown will be the glue that attempts to hold the All Blacks midfield together this year.