"We have been further in the competition," Villa told Marca post-match. "There are 90 minutes left in the tie and the result can be saved at home.
"We now have a break in the competition and we must focus on La Liga, but we have the talent to overturn the result."
The 29-year-old was also impressed by the speed of the Gunners on the counter-attack.
"Arsenal are a very good team," he added. "They caught us out on two occasions and caused us a lot of harm."