Kevin Magnussen admitted that Haas had made the wrong tyre choice for Saturday's sprint at the Autodromo Enzo e Dino Ferrari in Imola.
Coming into the weekend it appeared that most teams would run the medium tyre for today's 21-lap race. But that changed after they tried out the softer compound in a dry final practice session.
Confident that the red-walled tyres would be able to last the distance without significant drop-off, 17 cars started on the softs. Only Magnussen, his team mate Mick Schumacher, and Williams' Nicholas Latifi stuck to the mediums.
"I was super surprised to see everyone on the soft," he admitted when quizzed by the media in parc ferme after the end of the race. "We tried the soft in free practice and thought it would degrade too much.
"We did like 13 laps and it took a step around there of degradation, and I judged that it would continue,” he explained. “But looking at everyone else at lap 13, it was kind of the same.
"It took a little step but then stayed there and they had the same pace as me," he noted. “So the soft tyre was the right tyre, I got that wrong, but we live to fight another day.”
Starting from fourth place on the grid, it meant that Magnussen was lacking pace in the opening laps and quickly succumbed to attacks from Daniel Ricciardo and Sergio Perez.
"When everyone else was on soft at the start, I was a little nervous," he continued. “They obviously overtook me at the beginning.
"In the first part of the race they were faster, and then towards the end it kind of evened out," he added. Everyone just seemed to pass me at the beginning of the race and then it kind of reset so we were on the same pace, at least with Ricciardo and [Fernando] Alonso.
"But overall the soft tyre was the right tyre for that race, and we learned that."
Magnussen ended up dropping four places hy the finish, but by crossing the line in eighth he managed to pick up a championship point, and will duly start the Emilia Romagna Grand Prix from the fourth row.
“We would normally be happy with P8 in qualifying, so let’s look at the positives," Magnussen said. “We’ve had a good weekend [so far], looking forward to tomorrow and hopefully score some more points.”
“Maybe we expected a little bit of a better result," echoed team principal Guenther Steiner. "But it seemed that Kevin wasn’t really happy with the balance. All in all we scored a point, which is a positive."
On the other side of the Haas garage, Magnussen's team mate Mick Schumacher made better use of the medium selection and ended up gaining two places in the sprint race, meaning he will start the grand Prix from tenth on the grid.
"We definitely chose the right tyre," Schumacher insisted. "We had some good battles but unfortunately still not quite in the points, so hopefully for tomorrow we will be in a position to do that.
"Fighting with a lot of cars around us, one of them being Seb [Vettel] which was a great fight, was good fun. We’ll have to wait to see how it is with higher fuel, but everything we’ve learned from this morning was promising.”