The Premier League side fell behind to an early Ezequiel Lavezzi strike in the first leg of their quarter-final clash at the Parc des Princes, before Eden Hazard pulled them level from the penalty spot.
However, a David Luiz own goal and a stoppage-time strike from Javier Pastore left Chelsea with an uphill task in the return leg at Stamford Bridge next week.
Mourinho had opted to start the match without a recognised striker, leaving Fernando Torres and Demba Ba on the bench in the absence of the injured Samuel Eto'o, and Mourinho was scathing in his comments about his side's lack of firepower.
"We play against a great team full of fantastic players, especially the attackers," he told Sky Sports. "They are the kind of team that, with the players they have, out of nothing they can score goals.
"We are not a team full of talent to score lots of goals, especially at this level."
With the match level at 1-1, Mourinho opted to withdraw Andre Schurrle, who had been Chelsea's most advanced attacker, and introduce Torres.
"I changed at 1-1 because I thought that Fernando could give us more depth than Andre," he continued. "The team was comfortable with Andre, the team had good control of the game, good ball possession, Andre was tracking back, the team was quite comfortable.
"I thought Fernando could give us a bit more."
Despite the two-goal deficit, Mourinho has not given up hope of making the semi-finals.
"Nothing is impossible, but difficult," he insisted. "We have to try, we have to go with everything. Let's try."
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