Sebastian Vettel acknowledged "we failed" after Ferrari again failed to trouble Mercedes as Lewis Hamilton reigned in France.
Mercedes have won every Formula One race so far this season and the stunning run continued with Hamilton leading a one-two with Valtteri Bottas at the French Grand Prix.
Ferrari's Charles Leclerc at least held onto third, but Vettel had been hoping the Scuderia would make up some ground on their rivals.
Having finished fifth, he admitted that did not pan out.
"We wanted to close the gap to Mercedes and we did not, so, in that sense, we have to be honest [and say] we failed," Vettel said.
"But I think we tried everything we could. And Charles' podium is at least a little satisfaction.
"Like I said, though, the big goal was to come here and eliminate the difference to them. Unfortunately, our parts did not work as we expected."
Team principal Mattia Binotto was slightly more optimistic and added: "In terms of performance, we are not yet where we want to be.
"We knew this circuit would be tough for us and to finish with Charles right behind Bottas is encouraging.
"The developments we have introduced since the Spanish Grand Prix have allowed us to close the gap and we have shown that we are on the right path.
"Some of these updates have proved to be very useful, others unfortunately less so, but we know that we have potential to improve significantly.
"At this point, we are confident, aware that there is still a lot to do, but that we have the ability to develop the car and to be competitive on all tracks."