Rebellion LMP1 driver Neel Jani says the #1 crew is in "survival mode" following the practice crash that forced Bruno Senna out of this weekend's Silverstone World Endurance Championship round.
Senna broke his ankle when he crashed at Copse in first practice at Friday, ruling him out of action and leaving Jani and Andre Lotterer to compete as a pair in the #1 R-13 Gibson.
They had to sit out second practice, with their car only repaired in time to take part in final practice on Saturday morning.
After driving the car for the first time, Jani said the Rebellion is "very unpredictable" to drive and that he would not be taking any risks following Senna's accident.
"We are just in survival mode at the moment with our car," Jani told Autosport. "We only did three laps yesterday with Bruno.
"He had a shit day - he went out of the pits, got hit by a Ferrari, spun, had to come back in, put a new set of tyres on, first flying lap, he crashed.
"We had to rebuild the whole car, the crew did a good job, and this morning we are just learning.
"The car is kind of different to drive than what we are used to around here, it's not straightforward.
"The car is very difficult to drive on the bumps here. Both me and Andre were struggling a lot, it's very unpredictable to drive. It's not a car you want to risk anything [with]."
Jani added that sharing the car only with Lotterer in the race would be "manageable" and that Rebellion's targets remains beating SMP Racing to top privateer LMP1 honours.
He also said the recent adjustment in the Equivalence of Technology rules, designed to reduce Toyota's margin of dominance, would change little for Rebellion.
"On a flying lap it is clear that we have no chance against Toyota," he said. "Tomorrow we'll really see the truth, but still there is a gap.
"The EoT helps for sure, but we have other things to solve, still. It doesn't change, we still have to solve some stuff on our side of the fence.
"Even qualifying we'll have to treat as a practice session because me and Andre are still unhappy with the handling. Tomorrow will be a long day."
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