Jun.23 (GMM) Timo Glock sat out qualifying for the European Grand Prix.
On Friday in Valencia, the Marussia driver struggled through practice with a stomach bug he picked up mid last week.
"Back in the car today (Friday) I have felt a little better and I am hopeful that I am on the mend," said the German.
But Glock, 30, was still feeling unwell on Saturday, and was the slowest runner in morning practice after 16 laps.
Reports said he went to a local hospital for checks.
Marussia then announced in a statement shortly before qualifying that Glock will sit out the rest of Saturday's action.
"It is clear that at this time, he is not sufficiently well to take part in a demanding qualifying session and needs to recuperate further," the team said.
A decision about whether Glock will race on Sunday will be announced in the morning.