The Hurricanes are playing a warm-up game with the Crusaders on Saturday. Both teams will be careful what they reveal as they meet again next week in their opening DHL Super Rugby Pacific game.
Coach Jason Holland said Perenara was likely to be out of action for about a month.
He was still undecided on who will start at halfback in the first-round game. Jamie Booth, who has had a long injury break, will start in Saturday's warm-up game. Logan Henry, from Manawatu, had made an impact since joining the team, while Richard Judd and Leroy Carter, from sevens, were also performing well.
"They're all capable guys who have had a good pre-season with us and are clear on what we are trying to achieve," he said.
Holland said the competition for places in the starting XV and 23 was not confined to the halfbacks. There was plenty of competition among the loose forwards, even without Ardie Savea being available yet, and across the team.
"I'm really happy with how we've tracked over the last month and how people play tomorrow will play a big part in our 15 and 23 named for round one next week," he said.
Holland said he was pleased with the way his forward pack performed in last weekend's first warm-up game against the Blues. It was a chance to put systems and plans to the test and, while it was still early days in the season, some good work was evident, and they want to continue to grow that.
"It's a little bit niggly for us because we play the Crusaders again in round one next week. That's just the way it has panned out around Covid and the pre-season situation, but there's still a hell of a lot of things we can get out of our game around accuracy in our game and some physical parts.
"We're looking forward to it but we might hold a couple of things back for the following week," he said.
Holland said he wasn't a fan of the suggestion of having uncontested scrums if forced by Covid hitting sides. He said it would change the nature of games, and it would be quite possible to have backs appearing in the front row under those circumstances.