Ole Gunnar Solskjaer said he had no choice but to start Axel Tuanzebe and Alex Telles in Manchester United's clash with Paris Saint-Germain.
United begin their European campaign on Tuesday night when they face the French champions in Champions League Group H.
Tuanzebe starts his first game of the calendar year following injuries to both Harry Maguire and Eric Bailly, with summer signing Telles starting on the left flank as United revert to a back three with wing-backs.
Speaking ahead of the match Solskjaer reiterated he had little choice but to start the defensive pair due to injury issues at the back but is confident they can rise to the challenge against last season's runners-up.
"It's great to be back in the Champions League and be playing these games against the best teams in Europe," Solskjaer told BT Sport. "They have some of the best players in the world, this is what we worked for last season and what our players dreamed about.
"Every game you play is a chance to show what you are about. This is a test of character.
"We have put a team together that we feel is the best we can start with tonight. It's a game of 90 minutes of course. We have to look at the opponent and see what their strengths are. We've had a few injuries so Axel is back in for the first time in a long, long time and Alex makes his debut and what a stage to do it on.
"You can't have a moment where you blink against this team. They have pace, skill and are quick on the transition."
