Injuries, both fresh and persistent, have forced Martin to scratch a handful of players from the game.
Three Highlanders - first five-eighth Daniel Bowden (quad), No 8 Steven Setephano (calf) and openside flanker Alando Soakai (shoulder) - are out, as are former Otago fullback Craig Clare (ankle), Kaikorai flanker Adam Hill (back) and Southern flanker Carl Anderson (hamstring).
Both Bowden and Setephano needed a little more time to recover from the injuries that plagued them in the latter stages of the Super 14, Martin said.
"It's frustrating for Daniel because he's physically and mentally ready. He should be available for club rugby this weekend, but we've just been told he needs a little bit of time to rest it completely.
"Stephen has felt the calf tighten a bit, but I also hope he will play club rugby next weekend."
Clare remains a talent unfulfilled because of injuries.
He had just returned to club ranks after nearly a year out with a serious injury after wrenching his ankle on his "good" leg, Martin said.
Clare will be out another two or three weeks, and Otago is anxious to see him fit.
Fullback is not a position of great depth in Otago, and there have been glimpses of his ability.
The fullback match-up in the trial features the strapping Alipate Fatafehi, who has played 13 games for Otago mainly on the wing, and the more refined Casey Stone, playing alongside Alhambra-Union partner Karne Hesketh in the White team.
With incumbent Soakai and contenders Anderson and Hill absent, the battle on the openside flank will feature University A's Charlie Swart against Harbour's Eben Joubert, the recent arrival from South Africa.
Alhambra-Union captain Matt Clutterbuck joins the bench, something that will please his many supporters at the club.
Other tasty clashes include first five-eighth (Glenn Dickson v Chris Noakes), halfback (Toby Morland v Sean Romans), centre (Brett Mather v Ben Smith), lock (Tom Donnelly v Ross Kennedy) and prop (Jeremy Aldworth v Jed Vercoe).
Martin has deliberately put his Super 14 players - available for the trial for the first time - in one team.
"We've made it quite clear to the Highlanders that the other team includes a number of players who are snapping at their heels.
"We wanted to set the trial up so we got real competition. It will give us a much better gauge of where all the contenders are."
Another feature of the trial will be that is to be played with the Experimental Law Variations.
Most of the triallists have been playing under the old laws in club rugby.
The trial starts at 2.30pm and will be refereed by Keith Brown (Southland).
Otago trial
Clutha Rugby Club, 2.30pm
Otago Blue: Alipate Fatafehi, Charlie Tiko, Brett Mather, Aaron Bancroft (vice-captain), Lucky Mulipola, Glenn Dickson, Toby Morland, Kieran Williams, Charlie Swart, Shaun Tauti, Seko Qaraniqio, Tom Donnelly, Jed Vercoe (captain), Mason Pomare, James Cooper.
Reserves: Ben Perreira, Ben Nolan, Jonathan Direen, Fili Koloamatangi, Matt George, Matt Direen, Sam Young, Jeremy Cave, Dane Grey.
Otago White: Casey Stone, Karne Hesketh, Ben Smith, Dan Snee, Randall Kamea, Chris Noakes, Sean Romans (vice-captain), Paul Grant, Eben Joubert, Hoani Matenga, Uili Kolo'ofai, Ross Kennedy, Sam Hibbard, Peter Mirrielees (captain), Jeremy Aldworth.
Reserves: Sam Anderson-Heather, Cam Ward, Dane Maraki, Ash Johnson, Lewis Hancock, Luke Herden, Andrew Parata, Bevan Passmore, Matt Clutterbuck, David Taumoepeau.
