Tuesday 20 June 2017 08:01, UK
The Lions travel to Hamilton where the 2012 and 2013 Super Rugby champions lie in wait, four days ahead of the opening Test against the All Blacks.
Rory Best skippers the Lions on Tuesday, while the Chiefs are led by 2011 World Cup winner Stephen Donald.
We look at five talking points in what is a hugely important game for the Lions in the context of their tour.
Last chance to impress
Tuesday's clash represents the last chance for any of those involved to change Warren Gatland's thinking ahead of the first showdown with the All Blacks at Eden Park on Saturday.
The starting back three of Liam Williams, Jack Nowell and Elliot Daly could still be fighting it out for a seat on the bench for the Test-series opener, while Ireland flanker CJ Stander will also want to press claims to be in the back row picture.
Elsewhere, Wales lock Alun Wyn Jones takes a seat on the bench and will be itching to respond after Maro Itoje and George Kruis impressed in Saturday's 32-10 win over the Maori All Blacks.
Owen Farrell has been declared fit for the first Test, but it won't stop Dan Biggar making a play for the No 10 jersey.
Mid-tour call-ups with a point to prove
Much has been made of Gatland's decision to draft in six new players to his touring party.
The British and Irish Lions coach has come under fire for appearing to prioritise geographic proximity over meritocratic selection when he added Wales quartet Cory Hill, Kristian Dacey, Gareth Davies and Tomas Francis as well as Scottish duo Allan Dell and Finn Russell to his squad.
All six players have been named on the bench for the match in Hamilton and they will be keen to show they are worthy additions to the squad should they be called to the field on Tuesday.
Lions scrum-half Grieg Laidlaw jumped to their defence of the squad's newcomers earlier in the week.
"They are all Test match players," Laidlaw said of the new additions. "Warren's made it no secret this was his plan all along.
"It's something he did on the Australia tour in 2013. He thought it would be successful then, and it did indeed work, and now he's gone down the same track.
"So ultimately it's to look after the Test squad, which is so important now at this stage of the series.
"It's about looking after everyone to make sure we get the best performance in the Test matches when they come around."
Must-win for Lions
A defeat for the Lions would take their record in New Zealand to three wins from six games, but the effect of a potential loss would have a bigger impact than just that of their win-loss ratio.
The Chiefs' side has been severely depleted by both the All Blacks and the Maori All Blacks. The likes of Liam Messam and Hika Elliot - both named on the bench - featured in Saturday's loss to Gatland's side, but the Chiefs are still missing players such as Aaron Cruden, Sam Cane, Brodie Retallick, Anton Lienert-Brown, Charlie Ngatai, James Lowe, Damian McKenzie, and Tawera Kerr-Barlow.
With the pressure already on the Lions, a loss ahead of the first Test against a vastly under-strength Chiefs side would put the the tourists on the back foot ahead of an already difficult opening Test at Eden Park four days later.
Can Donald strike again?
A national hero thanks to his role in the 2011 World Cup, Donald abandoned his fishing holiday to kick the winning penalty and write himself into All Blacks history.
The 33-year-old then continued to establish himself as a cult hero when he captained the Chiefs against Wales last year, leading the Super Rugby side to a 40-7 victory.
Donald is one of five All Blacks set to face the Lions on Tuesday along with Nepo Laulala, Dominic Bird, Hika Elliot and Liam Messam, and has once again been asked to don the captain's armband.
Can history repeat itself for the Chiefs playmaker as he looks to add another impressive scalp to his CV?
Midweek games no less of an honour
Wales' Dan Biggar feels a big performance could put him in contention for a spot in the Lions' Test side, but even if it doesn't he says the game holds no less value for him.
With Owen Farrell and Johnny Sexton spearheading the Lions' tour in the No 10 jersey, Biggar has found himself at the bottom of the pecking order to start at fly-half against the All Blacks, but says rugby players around Britain and Ireland would love to trade places with him and have a chance against the Chiefs.
The 27-year-old says it is important not to lose sight of the importance of the badge.
"Whether it be here, which perhaps is perceived as a game which not everyone wants to play in, or whether you're playing in the deciding Test or first Test against the All Blacks, it should mean absolutely the world to you to pull this shirt on and represent it," said Biggar.
"For us as a group it's a huge opportunity. if we can put a good performance together, a good win, then it puts pressure on the coaches to make some harder decisions."
Chiefs: 15 Shaun Stevenson, 14 Toni Pulu, 13 Tim Nanai-Williams, 12 Johnny Faauli, 11 Solomon Alaimalo, 10 Stephen Donald (c), 9 Finlay Christie, 1 Siegfried Fisi'ihoi, 2 Liam Polwart, 3 Nepo Laulala, 4 Dominic Bird, 5 Michael Allardice, 6 Mitchell Brown, 7 Lachlan Boshier, 8 Tom Sanders.
Replacements: 16 Hika Elliott, 17 Aidan Ross, 18 Atu Moli, 19 Liam Messam, 20 Mitchell Karpik, 21 Jonathan Taumateine, 22 Luteru Laulala, 23 Chase Tiatia.
British and Irish Lions: 15 Liam Williams,14 Jack Nowell, 13 Jared Payne,12 Robbie Henshaw, 11 Elliot Daly, 10 Dan Biggar, 9 Greig Laidlaw, 1 Joe Marler, 2 Rory Best (c), 3 Dan Cole, 4 Iain Henderson, 5 Courtney Lawes, 6 James Haskell, 7 Justin Tipuric, 8 CJ Stander.
Replacements: 16 Kristian Dacey, 17 Allan Dell, 18 Tomas Francis, 19 Cory Hill, 20 Alun Wyn Jones, 21 Gareth Davies, 22 Finn Russell, 23 Tommy Seymour.
Watch Chiefs v Lions on Sky Sports 1 from 8am on Tuesday
