Williams drivers Pastor Maldonado and Rubens Barrichello were left lamenting their lack of running in practice for the Japanese Grand Prix.
The duo endured a difficult start to the weekend on Friday, with Barrichello managing just 11 laps in the morning and 14 in the afternoon. Maldonado stopped early in second practice because of an engine problem.
"I had limited running today, which was unfortunate," said Barrichello, 18th quickest. "In this morning's session, a puncture cut my session short and then an off this afternoon also put me out early. The car felt quite loose before the incident and so we have a lot of things to look into now."
Maldonado, who finished down in 21st place, added: "An engine problem caused me to stop early in P2. It's my first time at Suzuka so I really need some more laps. We'll have our work cut out in tomorrow's final session."
Williams said that, due to the lack of running, it will revise its program for final practice on Saturday.