On a day when a big haul of points was possible, Williams could only manage 13th and 16th places in a disastrous afternoon for the Grove-based team at Sunday’s Spanish Grand Prix.
A puncture on the first lap following contact with Fernando Alonso’s McLaren ruined Felipe Massa’s race, dropping him to the back after making an early pitstop.
He was then hit by the other McLaren of Stoffel Vandoorne on lap 33, bringing out the virtual safety car as the Belgian retired.
From then on all Massa could do was bring the car home, eventually finishing 13th.
But the Brazilian believes fourth could have been possible after Kimi Raikkonen and Max Verstappen were eliminated in a collision at the first corner and Valtteri Bottas retired with mechanical problems.
He said: “I’m so disappointed.
“I had a fantastic start, passing [Sergio] Perez and Alonso on the straight and then I got to turn one and saw the incident ahead.
“I got to turn two and Alonso was suddenly on the outside of the corner. We touched and I picked up a puncture, which ruined my race.
“We had a big opportunity to finish fourth, which I think I could have done because we had good pace.
“It’s really painful because we lost so many points as a team.”
It was an equally disappointing day for Massa’s team-mate Lance Stroll, who struggled with his tyres for much of the race and limped home to 16th and last.
The young Canadian had started 18th and while he didn’t suffer the dramas that Massa did, he just wasn’t able to find the pace in his car on the medium tyres.
He said: “It was not a great race. I have had better ones and I just found it frustrating.
“The start was good, as were the first couple of stints on the soft tyres and I had good pace at the beginning, but we just struggled on the mediums and started to lose grip.
“It was just one of those races, but I am sure it will be better next time.
“At every race I get more and more confident, but this weekend was just a tough one.”
Massa is ninth in the championship standings with 18 points, while Stroll has yet to score. Williams are sixth in the constructors’ table.
The next race is the prestigious Monaco Grand Prix on May 28.