Marcus Ericsson took the blame for his early exit at the Malaysian Grand Prix as he spun out of a top 10 position.
Having passed Max Verstappen on the opening lap, Ericsson tried to go around the outside of Nico Hulkenberg at Turn 1 but lost the rear end of the Sauber and ended up in the gravel.
"It is a very frustrating end to a good weekend," he said, having started from ninth place.
"I felt comfortable in the car straight away and had a good start during which I could make up one position. Nico must have had a good start as he was ahead of me, but I felt I had more pace than he did. When I tried to pass him down to Turn 1, I went for the move to the outside.
"I know it is possible to overtake there, but unfortunately I lost the rear, went off and got stuck in the gravel trap. Anyway, we need to take the positives out of this weekend, and I have learned from what happened in the race."
Team-mate Felipe Nasr was 12th and apologised for making contact early on with Kimi Raikkonen.
"We need to reflect and understand why we didn’t have enough pace," he said. "The race itself was not easy, as I had contact early on with Kimi.
"I should have avoided this incident, but it can happen sometimes when we are racing."