Kimi Raikkonen believes he had the pace to finish in fifth position in the Singapore Grand Prix, although he admitted sixth was a good result given Lotus's form.
"After the result in qualifying today's race was not too bad, but I think we had a chance to do a bit better," said Raikkonen, who had qualified in 12th position.
"We weren't quick enough to be fighting for the podium but the first safety car didn't help us and maybe we could have gained an extra place without that.
"We were definitely faster than Michael [Schumacher] and Nico [Rosberg] but we ended up stuck behind them for most of the race which was frustrating. It's so hard to overtake here that you have to rely on passing people in the pitstops or on someone making a mistake."
The Finn kept third position in the championship thanks to Lewis Hamilton's retirement, but he is aware that his team will have to get more performance out of its car in order to stay in the fight.
"I'm still third in the drivers' championship but we've got some improvements to make for the next races to be fighting with the cars in front," Raikkonen said. "Hopefully we can make a step forward in Japan and take it from there."
Teammate Romain Grosjean marked his return to action after his one-race ban with another points finish, crossing the checkered flag right behind Raikkonen.
"It was a tough race but not a bad result in the end," Grosjean said. "Our performance was much better than what we would have expected at the start of the weekend.
"Of course, I dropped a position to Kimi as well; he was quicker than me towards the end of the race and there was no sense in holding him up."