Three days after beating the Gunners in the Emirates FA Cup at St. Mary's, this time there are three points on offer for the winners on the south coast.
Saints prevailed in the fourth-round tie at the weekend, as an own goal from Gabriel proved enough to send them through to the last 16 of the FA Cup, and attention now turns to the second part of the double-header on Tuesday.
The Saints boss was a happy man after the performance on Saturday, but there are still areas he feels can be better in this next match.
"The good thing was the defensive work," Hasenhuttl told southamptonfc.com. "I think it was absolutely ok. We didn't give them a lot of chances.
"The chances we created were ok. I think there can be a few more, and then a little bit more clinical in the final pass and the final decision, but it's a strong side.
"We know that we need to have every part of our game being good on Tuesday night."
As well as progress in the cup, Saturday's result also game the Saints a fifth clean sheet in the past six games.
"We spoke last season that it is not possible to concede so many goals and this season is the first season where we are defensively in a different mindset and a different mentality on the pitch," said Hasenhuttl.
"We defend better as a team together and this is always the basis of everything."
Whilst Saints indeed defended extremely well throughout the 1-0 win on Saturday, Hasenhuttl is also expecting his opposite number, Mikel Arteta to make a few changes.
"Yes, for sure, because they have a very big squad and rested a few players on Saturday, so it can definitely be a different squad," said the Saints boss, who himself is without the injured Kyle Walker-Peters and suspended Ryan Bertrand.
"But, anyway, for us it doesn't change a lot, we are always more focused on us and our behaviours and that's the reason why that's not so interesting for me."