The result sees United reach the round of 16 4-0 on aggregate.
Tuanzebe said of his positional switch: "(Being played in midfield) is just something the gaffer did, we did not get the win but we are through.
"I am a versatile player, my natural place is central defence but I did it for the team. It is a while since I played in midfield but most important thing is that we are through.
"The season has been up and down for me and we need to get more minutes and momentum.
"This is Man United, all players who play for us are talented and the manager always has options. the personalities that United bring through are determined players and that shows when we get the chance to play.
"It takes a while to get momentum going, have faith in the manager and we are starting to build that. It is not something done in a year or two, it is a long project and having faith in the coaching staff. The results are coming through.
"The disappointments always stay with you and you do not want to feel like that again, you try your best and ensure it does not happen again."