With both Coles and Matu'u leaving the field injured against the Crusaders at Westpac Stadium, the final scrum was a no-contest affair, which hurt the visitors as they chased the victory.
Southland's Jason Rutledge, called in this week from his plumbing job by Hammett, will be the reserve hooker if Matu'u is ruled out.
Prop Jeffrey Toomaga-Allen has been bracketed on the reserves bench due to a sternum injury.
The Hurricanes team to play the Highlanders at Forsyth Barr Stadium in Dunedin is: James Marshall, Alapati Leiua, Conrad Smith (c), Tim Bateman, Julian Savea, Beauden Barrett, TJ Perenara, Victor Vito, Karl Lowe, Brad Shields, Jason Eaton, Jeremy Thrush, Ben May, Motu Matu'u/Ash Dixon, Ben Franks. Reserves: Ash Dixon/Jason Rutledge, Reggie Goodes/Jeffrey Toomaga-Allen, James Broadhurst, Faifili Levave, Chris Smylie, Tusi Pisi, Andre Taylor.