The touring squad features a 16-forward, 11-back split and also sees the return of first five-eighth Beauden Barrett, who missed the Hurricanes loss to the Jaguares on Friday night due to the second of his All Black rest weeks.
"We were obviously disappointed with the result against the Jaguares after what had been a good four week period for us," Plumtree said.
"The next two matches are vital for us in South Africa as we push for a home quarterfinal but we know the size of the challenge against two quality sides who are also fighting really hard for places at the top of their conference."
The Highlanders also have their depth bolstered for important games ahead, with coach Aaron Maguer confirming that Liam Squire and Jackson Hemopo will be available for their final two matches.
Squire, who missed the Highlanders' two defeats in South Africa due to personal issues, also played club rugby this weekend, and Maguer said he was ready to play his first Super Rugby game of the season.
"Both of those guys [Squire and Hemopo] will be available for selection," said Maguer.
"It's great for Liam to get out there and have a run around and also connect with the community.
"He is a good space so he'll be available for selection."