Celtic manager Neil Lennon relished the opportunity to give European experience to teenagers Karamoko Dembele and Scott Robertson in Thursday's defeat to Cluj.
Dembele, 16, came on as a 72nd-minute substitute in the 2-0 Europa League loss in Romania and became the youngest player to represent Celtic in continental competition.
Debutant Robertson started the match and played the full 90 minutes, with the 18-year-old coming in as one of nine changes to the side that beat Rangers in Sunday's Scottish League Cup final.
Celtic were already assured of top spot in Group E but saw a 12-game winning run in all competitions ended by goals from Andrei Burca and Damjan Djokovic.
"We think very highly of him," Lennon told Celtic TV of Dembele. "I wanted to give him some experience.
"I want to keep him around the team squad because we think he's a real talent. I wanted to give him a little bit of experience at this level.
"Scott Robertson also had a terrific debut. His performance delighted me. I thought it was a superb debut for an 18-year-old to come in and play in that environment so maturely and with a lot of composure."
Explaining his team selection, Lennon added: "The campaign was done and dusted and we’ve already won a trophy so I didn’t want to run the risk of injuries.
"I wanted to give others some experience and some will need that 90 minutes for the games coming up.
"We're disappointed to lose the game but in the main very pleased with what I got out of it. Some of my players needed the games and needed the 90 minutes.
"Overall, we’ve had an amazing campaign and I'm happy to have used the squad tonight because we have so many important domestic games coming up."