Described as the Rubik's Cube for All Blacks selectors, picking the right midfield combination to start at the Rugby World Cup could prove vital.
The All Blacks have plenty of options in the midfield with four players capable of starting in seven different combinations. Ryan Crotty and Anton Lienert-Brown can play both second five-eighth and centre, while Sonny Bill Williams is a specialist at 12 and Jack Goodhue at 13.
We take a look at the records of the All Blacks midfield combinations when they have started together.
12) Sonny Bill Williams, 13) Ryan Crotty
The incumbent pairing for so long, but a combination of injuries and, well, the general effects of aging has seen both struggle to hold their spots in the midfield. Two impressive victories on South African soil as well as the opening win over the British and Irish Lions. Just one defeat as a starting combo came against the Wallabies in Brisbane two years ago.
32-30 win v South Africa, Pretoria 2018 57-0 win v South Africa, Auckland 2017 25-24 win v South Africa, Cape Town 2017 30-15 win v Lions, Auckland 2017 23-18 loss v Australia, Brisbane 2017
12) Sonny Bill Williams, 13) Anton Lienert-Brown
Impressive in that must-win Bledisloe Cup decider against the Wallabies at Eden Park, with both running and defending well. Pairing was disrupted in that famous loss against the Lions in Wellington when Williams was sent off.
Notable games: 36-0 win v Australia, Auckland 2019 21-24 loss v Lions, Wellington 2017 (SBW sent off)
12) Sonny Bill Williams, 13) Jack Goodhue
The only unbeaten midfield combination, and one that perhaps gives the All Blacks the most game-breaking attacking potential. But both have struggled with injuries and form this year. And were not at their best in the draw against the Springboks in Wellington.
Record: 2 wins, 1 draw
Notable games: 16-16 draw v South Africa, Wellington 2019 16-15 win v England, Twickenham 2018
12) Ryan Crotty, 13) Anton Lienert-Brown
Given the task of starting the All Blacks' first match of the World Cup against the Springboks and passed with flying colours. Lienert-Brown, in particular, showed why Steve Hansen called him the most in-form midfielder of the bunch. The most experienced combination apart from the SBW-Crotty pairing.
Record: 8 wins, 1 loss
Notable games: 23-13 win v South Africa, Yokohama (RWC) 2019 36-34 loss v South Africa, Wellington 2018 57-15 win v South Africa, Durban 2016
12) Ryan Crotty, 13) Jack Goodhue
A solid and consistent combination. Struggled against Ireland's rush defence in their loss in Dublin in 2018.
Notable games: 16-9 loss v Ireland, Dublin 2018 38-13 win v Australia, Sydney 2018
12) Anton Lienert-Brown, 13) Jack Goodhue
Combination of youth and form over the last year suggests this is the All Blacks' ideal pairing on paper. But they have been rarely tested together, with the combo losing their only test in this year's loss against Australia in Perth.
Record: 1 loss
Notable games: 47-26 loss v Australia, Perth 2019
12) Anton Lienert-Brown, 13) Ryan Crotty
Another option is Lienert-Brown at 12 with Crotty at 13. However, these two have never started a test match together.
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