Williams performance chief Rob Smedley has insisted that the team's problems at the Monaco Grand Prix are a "one-off".
Felipe Massa will start the race from 14th, with his teammate Valtteri Bottas down in 17th after a disastrous qualifying session on Saturday.
The team are regular top-five contenders at other tracks, but Smedley has admitted that their car is not suited to the street circuit.
He told reporters: "We knew this wouldn't be the best track for us but we didn't expect it to be this difficult. We tried plenty of things with the tyres this weekend and still we are struggling.
"But we will be back to normal kinds of tracks soon so I'm not worried about the rest of the season. We didn't bring any updates here but we know we will have updates for the next two races.
"Hopefully this is a one-off and tomorrow it's just important for us to minimise the damage. Any points we can get tomorrow is good."
Williams have not qualified in the top 10 for the famous race since 2011.