The franchise has called in the brother of Lima Sopoaga, a forward who is yet to play a first-class game in New Zealand.
Tupuo Sopoaga (24) has linked with the franchise after joining the Woodlands club in Southland and signing with the Southland Rugby Union.
Highlanders chief executive Roger Clark said it was unusual to have signed up Sopoaga, a former NRL player, but these were different times.
"Usually what would happen was he would go and play with a club team and then, if good enough, play for Southland, and then if he was up to it we would look at him,'' Clark said.
"We have got a lot of injuries and there is not a lot around. With the rules we work around we have to have a certain number of players at training."
Otago loose forward Adam Knight has been in and out of the training squad all season. Clark said loose forwards were thin on the ground. The next cab off the rank after Sopoaga in the loose forwards was youngster Slade McDowall.
He injured his ankle in the first two minutes of a national colts trial and was out for a few weeks.
Clark said it was just a sign of the times with so many injuries. The Highlanders had 15 players injured a couple of weeks ago though some had since come right.
Sopoaga, a loose forward, played for New Zealand Schools in a test in Dunedin in 2010 alongside players such as TJ Perenara and James Lowe.
But he signed to play league in Australia at the end of that year and went to the Bulldogs before playing for Cronulla and Penrith.
He got no game time for Penrith last year so went across and played rugby in the national domestic competition in Australia.
Clark said Sopoaga was worth a try and had impressed so far. If there were further injuries he may get a look-in.
The Highlanders have loose forwards Shane Christie, Dan Pryor, James Lentjes and Liam Squire out injured, and Luke Whitelock missed the start of the season with a shoulder complaint.
Southern first five-eighth Josh Ioane has also been added to the squad. He is another player who has yet to make his first-class debut.
