"There is no better way to test people but to throw them into the arena. You are playing against players who will exploit any weakness."
One of Ireland's biggest challenges will be trying to contain the imposing Nemani Nadolo.
He returns to the left wing, having missed Fiji's 19-10 defeat to Italy.
Nadolo scored two tries for Montpellier against Leinster in Dublin last month in the Champions Cup.
Ireland: Andrew Conway, Darren Sweetnam, Chris Farrell, Stuart McCloskey, Dave Kearney, Joey Carbury, Kieran Marmion; Jack Conan, Jordi Murphy, Rhys Ruddock (captain), Devin Toner, Ultan Dillane, Andew Porter, Rob Herring, Jack McGrath. Reserves: James Tracy, Cian Healy, Tadgh Furlong, Kieran Treadwell, CJ Stander, Luke McGrath, Ian Keatley, Robbie Henshaw.
Fiji: Kiri Murimurivalu, Timoci Nagusa, Jale Vatubua, Lepani Botia, Nemani Nadolo, Ben Volavola, Henry Seniloli; Nemani Nagusa, Akapusi Qera (captain), Dominiko Waqaniburotu, Leone Nakarawa, Api Ratuniyarawa, Manasa Saulo, Talemaitoga Tuapati, Campese Ma'afu. Reserves: Sunia Koto, Peni Ravai, Kalivate Tawake, Sikeli Nabou, Perceli Yato, Semi Kunatani, Nikola Matawalu, Asaeli Tikoirotuma