Off the back of consecutive Q3 appearances for the team in Bahrain and Jeddah, Magnussen failed to make it out of Q1 in Melbourne and lines up 17th, while Mick Schumacher will start 15th.
But rather than the performance being a concern that the team has lost its early-season potential, Magnussen says the result can be traced back to the team not getting on top of its set-up from the off in practice.
"I think we just didn't really nail the start set-up for this track," he explained. "It was a bit different to what we expected.
"We expected it to be kind of similar to the old track, but it's actually fairly different, and I just think we missed the starting set-up, and then had a pretty long way to go to get to a good spot with the car.
"I think we got close to it in qualifying, but then qualifying was just a mess with red flags and all that. So it just hit us in a bad spot and then I was out in Q1. So that's a bummer.
"But I think you can overtake on this track, and I do think we made the car slightly better. We're not where we were in Bahrain and Jeddah, but I think we're closer than when this weekend started. So I'm fairly positive. And you know, still looking forward to the race tomorrow, I think we can move forward."
Magnussen believes that with F1's midfield so competitive this year, the consequences of not getting the set-up spot on can be quite dramatic.
"I think with the field this year, if you miss your window a little bit, you'll see it very visibly in the results because it's closer this year," he said. "So I'm not panicking. I think we missed that window this weekend.
"But I think we made some good steps forward, and just didn't really have anything to show for it in qualifying. But I'm optimistic that the race will be better. And you can overtake here a little easier than you could in the past. So I'm looking forward to a fun race tomorrow."
Haas boss Gunther Steiner said the entire weekend had been a difficult one for Haas, as a run of small issues had left it unable to get on top of things as well as it had in the first two race weekends.
"I think the whole weekend just was always little things," he said. "Starting with Kevin not being well yesterday, then having a problem with the rear suspension on Mick. And then we just, in my opinion, we didn't get the tyres to work properly, the C5. We didn't get them to switch on.
"A lot of people out there are struggling with the car being unpredictable, so I think it's just one of these weekends where you say: what was wrong? I don't really know, but it was everything a little bit, and it just was not a good execution for the weekend."
