On Thursday the Spaniard, who suffered the injury after a friend rode over his finger after he had fallen from a dirt bike, passed the required fitness tests and will now take his place on the grid for his home GP despite undergoing surgery just days earlier.
"[On Friday] I will try (in practice) and we will see. It will be painful as the operation was only on Saturday evening," Marquez explained.
"Maybe we will suffer more than in other races but here in Jerez in front of the fans I have extra motivation and that can help me."
The Repsol Honda rider has endured something of an indifferent season thus far, claiming just 36 points from the opening three races of the campaign to sit 30 points off the pace set by championship leader Valentino Rossi.