Piotr Zielinski had opened the scoring for the Italians after 29 minutes in Spain but Torres levelled just earlier than the hour from the spot after a Juan Jesus handball.
The draw leaves the tie open for both groups to advance to the last sixteen of Europe's 2d-tier membership competition with the second one leg next week in Italy.
"They were given into our area a couple of times and they scored a purpose, we had a whole lot of possibilities," stated Barcelona skipper Gerard Pique.
"The feeling is ideal, the result now not so much. Everything stays open. It changed into a wonderful match in opposition to a high-stage opponent.
"The end result isn't first-class, we'd have favored to have had a bigger advantage for the go back in shape."
Barcelona are playing the Europa League for the first time in 18 years after crashing out of the Champions League within the group stage.
February 17, 2022
