Villa were comfortably beaten 2-0 at Villa Park on Sunday - a loss that could have ended with a far greater margin in favour of the visiting Reds side.
Delfouneso is confident Alex McLeish's squad have the character to bounce back against the Gunners, and says the disappointment is already forgotten ahead of their next Barclays Premier League encounter.
"There's no time to sit around now," he told the club's official website. "We have another big test on Wednesday and we have to get ourselves ready for it. We will get ourselves together and regroup.
"With the character we have in the dressing room, we will be raring to go on Wednesday. We have bounced back before and we can do it again, definitely.
"We will digest this result and then go on to the training pitch in the next couple of days and prepare for the next big challenge.
"Like Liverpool, Arsenal are a very good side. We must make sure we turn up and give them a really good game."
Delfouneso isn't underestimating the threat that Arsenal will undoubtedly pose, but remains optimistic about Villa's chances of getting back to winning ways on Wednesday evening.
"They are on form, even though they lost like us at the weekend and it won't be an easy game," he added. "But we have the necessary fight and spirit to get a result.
"We want to give the fans an early Christmas present - a good performance and hopefully a victory and also make it an entertaining game.
"I am confident and the boys are confident in the changing room that we can go and get the victory."