Romain Grosjean believes he could have gone through to Q3 in the Malaysian Grand Prix had he stopped for fresh wet tyres.
The Frenchman proved that Lotus was making progress as he finished Q1 with the 11th quickest time.
But he failed to match that promise in the second segment after not opting to pit for fresh wet tyres, as many of his rivals did. He dropped down the order later to finish 16th.
Speaking afterwards about what happened, Grosjean said that the team had been so focused on finally being able to deliver some pace from its car after a troubled start to the campaign that it did not think hard enough about the benefit of new rubber.
"It was the first time we have run the car in the wet," he said. "Q1 was pretty good, and I was happily surprised. It was the same at the start of Q2.
"We were P10/P11, and the grip was there, but the tyres dropped. We did not have enough of a look at it to know we had to pit, and change tyres.
"I did not know how much time we had left. The visibility was quite poor and I didn't know which tyres we should put on.
"But my extremes were completely gone and the grip was gone, I tried the last lap 150% - and almost went off three times before I spun."
When asked if he reckoned a shot at Q3 was on if he had changed tyres, Grosjean said: "It would have been on the edge, very close or possible.
"To have changed tyres afterwards is easy to stay, but we were trying to get the state of charge management, the turbo and the car working properly, and all that kind of things.
"It is the first laps we have done, so it is hard to just focus on which tyre to choose."
Team-mate Pastor Maldonado reckons he could have got through to Q2 if there had not been the late red flag for Marcus Ericsson's crash.
"Q2 was possible [without the red flag]," said the Venezuelan. "I was gaining quite well. All the data said that we would be able to get there.
"For sure, it's a lottery when it's raining. We are not only looking to be in Q2, we wanted to be a bit more forward. But it's a good starting point."