Williams Head of Performance Engineering Rob Smedley says the team must "knuckle down" and work effectively as it bids to improve, following a difficult run of races for the squad.
Williams has scored only 13 points across the past four races, falling substantially behind Ferrari and Red Bull, and instead coming under pressure from Force India.
Valtteri Bottas collected two points courtesy of ninth place in Hungary while Felipe Massa was only 18th amid a problem with his steering rack.
"I’m disappointed with that result," said Smedley.
"We had to work very hard for those two points. I think we achieved the maximum we could with Valtteri, he drove a solid race, but the pace of the car is just not there.
"After Felipe’s accident yesterday the car was out of balance and he just couldn’t get into a rhythm. Starting from 18th with an un-balanced car was always going to be difficult.
"He had a steering rack issue, after we had to re-build the car following his crash in qualifying, which meant the steering was off centre and was heavy in right-hand corners.
"We had to try and get it fixed before the race, both in the garage and on the grid. The guys did a very commendable job.
"These are tough times for the team. We have to knuckle down, be introspective, work as a team and start to understand how we’re going to get more performance from the car."