The 56th-minute strike was cancelled out 15 minutes later when Andres Iniesta played in Neymar, who curled an exquisite shot round goalkeeper Thibaut Courtois from a tight angle.
"We are satisfied because I think we played a good match," said Courtois "We scored a brilliant goal and then we defended very well.
A 1-1 draw is a good result and at the Calderon I think anything is possible. With our fans behind us it's like having an extra player and hopefully we can put on a good performance."
Atletico lost their talismanic striker Diego Costa to injury early on but still had the better chances in the first half through the former Barcelona forward David Villa.
It has been a remarkable season for La Liga leaders Atletico and they showed typical resistance before Barca found a way through.
"The game was what we were expecting with a very intense Atletico team," said Xavi, the Barcelona captain. "We had our chances to score and it was a shame they scored that fantastic goal. Barca deserved to win. We had more scoring chances but they work very hard in defence and it was very difficult for us to break them down."