The England midfielder brushed off attempts from the Brazilian to be handed the ball before spurning the chance himself to equalise in their Champions League opener.
Frank Lampard backed the 25-year-old though, insisting he is the penalty taker when he is on the pitch.
And Barkley remains undeterred about future opportunities.
“If there was another penalty in the game I would have been confident of taking it,” Barkley said.
“You can miss penalties. It’s not the end of the world. We’ve got five more group games to go that we’re aiming to win. Today just didn’t go our way. It’s disappointing really.”
Barkley insists discussions before taking the spot kick were not over who should take it, but rather to encourage him to score, with the hosts trailing thanks to Rodrigo’s goal.
“They were just encouraging me, encouraging me to score the goal,” Barkley revealed. “They are confident of taking penalties as well but I take penalties every day, I don’t miss them in training and in pre-season I was scoring penalties.
“I’ve missed penalties before, when I was at Everton. I’m gutted I missed but these things happen.
“We’ve got a lot of good penalty-takers in the squad. On a sheet in the changing room it says I’m on penalties when I’m on the pitch, otherwise it’s Jorginho.
“It’s more: ‘Good luck with the penalty’ type of thing, encouraging me. They would have been willing to take it as well but I felt confident.”
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