Poland have axed Grzegorz Walasek from their World Cup side and have brought in Krzysztof Buczkowski for the race-off.
The Poles were shocked by Russia in Saturday's World Cup opener in Bydgoszcz as they finished second.
Walasek endured a torrid time and was booed by the homes fans as he struggled to just two points.
The defending world champions now need to come through the race-off on Thursday in Malilla if they want to defend their crown, and they have moved quickly to change their line.
Buczkowski, who rides for Peterborough Panthers in the Elite League, will now line-up alongside Tomasz Gollob, Maciej Janowski and Piotr Protasiewicz.
Poland team boss Marek Cieslak told PAP: "An alternative choice is not simple, but due to the fact that Krzysztof Buczkowski has been with us since the very beginning, he practised and has everything ready, he will go with us to Malilla.
"I can say only that I regret the decision to select Walasek in Bydgoszcz, but so what? Now we go and fight in Sweden."
Looking ahead to what will be his SWC debut, Buczkowski said: "I am glad that I'm going to Sweden, I've got a chance and I want to take it together with the team. These are meetings where everyone must go just as well; the responsibility falls on all of us.
"The Malilla track generally favours me - at least it has this year. Typically, it is a grippy surface, but in the Race Off it may be quite different. I will need to do a little work in practice, but I believe it will be fine."