While his Saints side is known to press with intensity, Marcelo Bielsa' s Leeds are 'even more aggressive' according to the Austrian.
He came out on the losing side in both encounters with Bielsa last season and knows full well what kind of challenge he will be met with on Saturday afternoon. But whereas a number of opposition bosses and pundits have noted the entertainment value in Leeds' style of play, Hasenhuttl suggests this game might not be one for the neutrals.
"I think [you take into the game] nothing that you don't already know [about them], it's maybe one of the most intense games of the season," he said.
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"The average passes opponents play against them is the lowest in the whole league. When we speak about pressing and our shape, they are even more aggressive and do it for all 90 minutes. It will be not always nice to watch, with a lot of mistakes in the game because of the pressure both teams put on the other side. If you expect a five-star dinner you will not see it, it's more about winning duels, winning second balls, coming out of the pressure as quick as possible, using the space you get for a short moment properly. That means there will be a lot of bad passes included I'm sure. This is the way they play and we have to find the right answer, prepare for everything they offer us and go win the duels and the fights."
Southampton, like Leeds, have encountered issues in attack when teams defend in a low block, but thrive when there is space to be had. Although Leeds have been criticised in the past for being too open and pouring forward with reckless abandon, Hasenhuttl sees them differently.
"They are also a team that always have very good resting, getting lots of players behind the ball, never really exposed so it's quite hard to have a serious counter attack," he said.
"There are some options. The team who scores the first goal is definitely in a very good situation because it gives them more space for counter attacks, which both teams like to have. It's important to have a good start."
The last trip to St Mary's for Leeds was played in front of around 8,000 fans as Covid-19 restrictions began to relax. On Saturday the 20-year-old stadium will be open for a capacity crowd, with thousands of Leeds fans in attendance rather than the handful who somehow managed to gain entry to May's clash.
Hasenhuttl wants the home supporters to ensure their presence is known to Bielsa's side.
"It's important our supporters know what's coming up and give us their support," he said.
"We want to be the best on the pitch, they can be putting pressure on the opponent so it's not so nice to come to St Mary's and take points. This is what we need to have. A very committed performance from our side, the fans, from everybody."