The Ligue 1 leaders led through Javier Pastore's ninth minute goal, but Saber Khlifa's equaliser on the stroke of half-time made it 1-1 and the score remained the same at the end of extra time.
Zlatan Ibrahimovic was among those players to miss from the spot as PSG were knocked out of the competiton, but while Moura has revealed the sadness inside the dressing room, he says his attentions are now firmly fixed on securing the league title.
|5/2||Lucas Moura is 5/2 with bet365 to score anytime against Nice on Sunday
"I'm unhappy I didn't participate. I wish I could have been there but I didn't train correctly before the game. We had everything in our hands to win the game but in the end it was too difficult. We will now focus on the league.
"We had two great games against Barça. We were eliminated without losing. I don't think that this outing broke our momentum. We're proud of the character we showed and cannot wait for next season."
The midfielder signed a pre-contract deal with les Parisiens last summer and saw out Sao Paulo's league season before completing his move to France in January and he is confident his transition to life in Europe has been a positive one.
"I adapted very quickly. It's important but I’m here to help the team even without scoring. I adapted well and I take French classes twice a week but there are a lot of languages spoken in the dressing room. Italian, English, Spanish, I often lose focus. There are still lots of thing to do."
Moura has made 14 appearances for the club so far and set up three goals, though he is yet to open his account for PSG.
|James Richardson, Les Ferdinand & Goal.com's Peter Staunton run through the biggest tranfser talking points of the week.
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