Sunwolves not a one-man show
Inside centre Harumichi Tatekawa will wear the captain's armband in the Super Rugby newcomers' adopted home of Singapore, while Takeshi Kizu will start in Horie's position at hooker.
Describing Horie as "Mr Perfect", Tatekawa said he will have to lead the team his own way.
"He (Horie) is kind of like Mr Perfect," the stand-in skipper said.
"He can talk well, he can perform well and he can lead the team.
"It's something that I can't always do so I will have to play to my strengths and lead the team in my way."
Hammett said that while Horie was not injured he was feeling the effects of making nine consecutive starts and needed to be rested.
"We've had a lot of players with a high workload, not just in this Super Rugby campaign," said Hammett.
"For me, if I had more luxury of players, I'd give guys like Haru (Tatekawa) and Shota a lot more time off because they shoulder a lot of the leadership, not just on but off the field."
Hammett also praised Tatekawa as an "exceptional character".
Speaking to AFP after a pre-match press conference, Hammett said his side would need to play to their full capabilities to win – and avenge a 46-19 defeat by the Stormers last month in Cape Town.
"Just because you're playing at home or in a place you're familiar with doesn't achieve results. That's probably what happened a wee bit last week," he said.
The Japanese newcomers crumbled 22-40 to Australia's Western Force in their last outing after halting their seven-match losing streak with a 36-28 victory over Argentina's Jaguares.
"We're not good enough to ever get overconfident. Sometimes we can bring a hundred percent game but another team like the Stormers can bring that too and we will still lose by 30 to 40 points, that's the reality," Hammett said.
"But if we can bring our game and put them off theirs, or they don't quite turn up, anything can happen."
Based in Tokyo, this is the Sunwolves' last of three "home" games in Singapore, as rugby continues its push for more Asian fans in the build-up to the 2019 World Cup in Japan.
