The 31-year-old suffered nasty burns to neck and elsewhere. But reports suggest he is hoping to ride in Sunday's race.
If he does recover in time, he will line up on the second row of the grid at his home race.
Britain's Chaz Davies set a new qualifying record at the MotorLand Aragon circuit as he claimed Superpole for race one at the third round of the Superbike World Championship.
The Welshman is joined on the front row by double world champion Jonathan Rea (Kawasaki) and fellow Brit Tom Sykes, who followed him closely throughout the third practice session.
Italy's Marco Melandri (Ducati) was hot on Sykes' heels in fourth and lines up alongside Spanish duo Fores (Ducati) and Jordi Torres (BMW).
Fores was not the only one who had a qualifying session to forget, however. Randy Krummenacher, Ondrej Jezek and Markus Reiterberger all had crashes in quick succession.