The two, who have been impressive across junior and senior provincial competitions in the last year, will line up in a match 23 which sees centre Wandisile Simelane and Jordan Hendrikse make their return to the starting XV.
“We’re excited to see how Ruan and Quan go tomorrow," said Van Rooyen.
"It’s an extended opportunity for them to immerse themselves into our system and ultimately express their talent on the big stage."
Van Rooyen further went on to comment on the privilege of touring as a team, but at the same time focusing on the job at hand come the weekend: “Touring is always a great opportunity for the guys to strengthen bonds and build on our character which bodes well for team culture and ultimately on-field synergy.
“In terms of our approach tomorrow night, the catalyst for us will be the ability to adapt our style of play and our decision making at key moments during the game.”
Van Rooyen is optimistic about his side’s set piece play despite the challenges at lock, with a considerable amount of his jumpers out due to injury.
“The focus will be ensuring we get accurate lineout ball to create a platform for us to launch our attack and hold onto possession for as long as we can. Leinster is a side that thrives on getting their hands on the ball,” he concluded.
Elsewhere, Lunga Ncube and Nico Steyn are in line to make their competition debuts after being included on the bench for the match, which kicks off at 21h35 (SA time) and will be broadcast live on SuperSport.
Emirates Lions: 15 Quan Horn, 14 Stean Pienaar, 13 Wandisile Simelane, 12 Burger Odendaal, 11 Edwill van der Merwe, 10 Jordan Hendrikse, 9 Morne van den Berg, 8 Francke Horn, 7 Ruan Venter, 6 Jaco Kriel (captain), 5 Ruben Schoeman, 4 PJ Steenkamp, 3 Carlu Sadie, 2 Jaco Visagie, 1 Sti Sithole. Replacements: 16 PJ Botha, 17 Morgan Naude, 18 Ruan Dreyer, 19 Lunga Ncube, 20 Sibusiso Sangweni, 21 Nico Steyn, 22 Manuel Rass, 23 Tiaan Swanepoel.