Antonio Conte's side put in an impressive performance in Tuesday's 1-1 draw at Stamford Bridge and took the lead just after the hour through Willian, who had already struck both posts in the first half.
But with 15 minutes remaining the La Liga leaders took advantage of Andreas Christensen's wayward pass, Andres Iniesta getting in ahead of Azpilicueta to tee up Lionel Messi to sweep home in clinical fashion.
Conte felt Chelsea were close to the perfect game against Barca, and Azpilicueta is hoping for a greater deal of fortune in the return at Camp Nou in three weeks.
"[We approach the game] like we played today, we created more chances," he told reporters.
"They control the ball, that's normal, that's how they play. We created the most dangerous chances and we were the ones that could have won.
"We have to defend as a team and we must attack and hurt them like we did today. We hope to get better luck in Barcelona."
Thibaut Courtois and Marcos Alonso echoed the sentiments of their team-mate, the goalkeeper pointing to the obvious threat posed by Barca's talisman.
"We have to defend well, we will try to keep Messi as far away as we can from the goal, and then I believe we have the level to go forward and to score and to make them doubt," Courtois said.
"We know playing in that stadium is very hard, they have great games where they score a lot but it's my task to avoid that."
Alonso added: "For sure, it will be more difficult than today, there. As a team we're satisfied with this match and excited to go there.
"Barcelona is the favourite, especially in their stadium. But, we don't give up and Chelsea will face them there."