The 20-year-old is on loan from Barca and takes on his parent club in a key La Liga clash on Saturday.
Deulofeu said he was unfazed about taking on Luis Enrique's men, who are second and two points above Sevilla.
"We're going to do our job. They have some very good players, but it is what it is," he said.
"Barca and Madrid make all the best signings, but if we're fully focused we can hurt them. It's just another game, we aren't making too big a deal of it.
"I know it's a different kind of game, but I'm relaxed and we're going to go out and play our game."
Deulofeu said his focus was on Sevilla, who are in contention for a top-five finish.
"Like I said at the start of the season, I don't want to talk too much about Barca because I'm at Sevilla, I don't need to talk about another club," he said.
"I'm at Sevilla right now, I'm fully focused and learning here. We'll just have to see what happens next year."
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