Lucas de la Rua will make his competitive debut as Cardiff kick-off their Investec Champions Cup campaign against Stade Toulousain on Saturday (15:15).
The 19-year-old is handed the number seven jersey for the Stade Ernest Wallon opener, with Ellis Jenkins suspended and Gwilym Bradley, James Botham and Thomas Young all ruled out through injury.
De la Rua, who starred for Wales U20s in the summer, is one of seven changes for the trip to face the five-times European champions.
He is joined in the back-row by Mackenzie Martin and Shane Lewis-Hughes, who returns to the starting line-up. Teddy Williams also comes into the second-row, while Rhys Carré and Efan Daniel are brought into the front-row.
In the backs, Ben Thomas has recovered from an ankle injury to partner Willis Halaholo, while Jacob Beetham, who made his debut against Toulouse two years ago, starts at full-back.
Cardiff Rugby head coach, Matt Sherratt said: “It’s brilliant to be back in the Investec Champions Cup and we travel to France with no fear.
“It’s a competition where you play the best teams, with the best players, in the best stadiums and Toulouse are certainly one of them, but what an opportunity.
“They are a top-class team, who bring a huge amount of physicality with one-up carriers and a dangerous offloading game but we have to focus on ourselves and I don’t think they will have faced our playing style in the Top14.
“If we can get some continuity and speed of ball to play our own attacking shape then we can cause them a lot of problems.
“We have a lot of young players involved, and a mix of youth and experience, but we will have a real crack at them. There is no reason why we cannot be very competitive before returning to the Arms Park to face Bath.”
Alun Lawrence is named among the replacements and is in line for a first appearance in Blue and Black since returning to the club, while Harri Millard and Owen Lane have both recovered from injury to provide back-line cover.
Cardiff Rugby: Jacob Beetham, Josh Adams, Willis Halaholo, Ben Thomas, Mason Grady; Tinus de Beer, Tomos Williams, Rhys Carré, Efan Daniel, Keiron Assiratti, Rory Thornton, Teddy Williams, Shane Lewis-Hughes, Lucas de la Rua, Mackenzie Martin.
Replacements: Evan Lloyd, Corey Domachowski, Rhys Litterick, Josh Turnbull, Alun Lawrence, Ellis Bevan, Harri Millard, Owen Lane
Unavailable for selection: Gwilym Bradley (foot), Taulupe Faletau (arm) Theo Cabango (shoulder), Ciaran Parker (hamstring), Thomas Young (calf), James Botham (hamstring), Aled Summerhill (hamstring), Matthew Aubrey (calf), Lopeti Timani (concussion), Ellis Jenkins (suspended)