Per Mertesacker said Arsenal deserved to lose against Barcelona after failing to convert their chances in a 2-0 defeat at the Emirates on Tuesday.
Alex Oxlade-Chamberlain and Olivier Giroud had the best chances for Arsenal in either half before Lionel Messi's two late goals left the Gunners on the verge of Champions League elimination in the round of 16 for the sixth year in a row.
"We had to score at one point here, and that's why we do not deserve anything," said Mertesacker, who was partially at fault for the penalty decision that gave Messi his second goal.
Arsenal did well in containing the threat of Messi, Neymar and Luis Suarez for the first 70 minutes despite Barcelona dominating possession. But they were caught on the counter-attack for Barcelona's opening goal and Mathieu Flamini then brought down Messi in the area just a minute after coming on.
"You would never keep them quiet for 90 minutes, that was for sure," Mertesacker said. "We managed it well in the first half. In the second half as well, we had a good period with a couple of chances. We needed to score, then we can drop back.
"We took more risk and obviously then they scored. It's going to be much more difficult, but we never give up. We tried our best, but we didn't deserve it because we had enough chances to score at least one."
Aaron Ramsey echoed those comments, saying: "I thought especially in the first half we've done really well. We created a few opportunities, but we didn't manage to take any. As soon as they scored, it's going to be tough for us now. But we'll go there and try our hardest."
Goalkeeper Petr Cech said there was little difference between the Gunners and Barcelona until Messi broke the deadlock.
"It's frustrating. It's disappointing because we've done so well in the game. We created some chances and I thought the difference between the two teams wasn't [big]," he said. "They managed to find the goal and that made the biggest difference in the game and then the second goal from the penalty made our task even harder for the away game.
"But I thought we've done really well and the only thing we didn't do so well is we didn't take our chances. In games like this you need to be more clinical and when you have a chance you need to find the back of the net."
Arsenal will have to rebound quickly with Manchester United coming up in the Premier League this weekend as the Gunners turn their focus back to their main goal for this season.
"We have to concentrate on the Premier League now. Then in month we're facing Barcelona again with the same courage and with the same bravery," Mertesacker said.
"We still have a little chance, we don't give up as a team. We always fight, that's our spirit, and we keep going like that."