Labuschagne, who recently became eligible to represent Japan, will pack down next to their captain, Michael Leitch, and the experienced Amanaki Mafi in the Brave Blossoms’ back row.
Japan coach Jamie Joseph, who represented New Zealand in his playing days, said they are expecting a very tough encounter against a strong Springbok team.
“We are under no illusions how tough it will be,” said Joseph.
“We are playing probably the biggest line-out in world rugby and they’re preparing to play the All Blacks.”
Joseph said the match against the Boks is part of their preparation for the Rugby World Cup, which Japan hosts from 20 September to 2 November.
“That’s part of the reason we wanted to play South Africa,” said Joseph.
“It’s the final page in our preparation, but it’s not a must-win game – the next game [against Russia] is a must-win. It’s about performance. If we perform we will create a winning opportunity and that’s our focus.”
Japan: 15 William Tupou, 14 Kotaro Matsushima, 13 Timothy Lafaele, 12 Ryoto Nakamura, 11 Kenki Fukuoka, 10 Yu Tamura, 9 Kaito Shigeno, 8 Amanaki Mafi, 7 Lappies Labuschagne, 6 Michael Leitch (captain), 5 Uwe Helu, 4 Luke Thompson, 3 Koo Ji-won, 2 Atsushi Sakate, 1 Keita Inagaki. Replacements: 16 Takuya Kitade, 17 Isileli Nakajima, 18 Asaeli Ai Valu, 19 James Moore, 20 Yoshitaka Tokunaga, 21 Yutaka Nagare, 22 Rikiya Matsuda, 23 Ataata Moeakiola.