With Vettel at the back of the field, Raikkonen will lead Ferrari's charge after missing out on pole by a mere 0.045 seconds.
Engine problems for Vettel's Ferrari denied him the chance to set a lap time in Saturday's qualifying session - and could prove to be a huge moment in the championship race. We are going to have a tough race against these guys, particularly the Red Bull pair as they had good long run pace yesterday and today.
An inspection of the auto back in the Ferrari garage appeared to indicate only a minor issue but efforts were ultimately abandoned, leaving the German driver to start his race tomorrow from the back of the grid.
"So we have some work to do if we want to be on the front row tomorrow".
"I think it's going to be very close in the next races", said Hamilton, who has won every grand prix since the mid-season break, after celebrating his 60th career victory.
Asked to explain that contradiction, the Briton said in Malaysia: "Racing really gives me more pleasure than ever".
He went to Singapore three points adrift of Hamilton, starting from pole at a track that suited the Ferrari, and would have expected to regain the title lead.
"I'm sorry for what happened to Sebastian because obviously he was very quick through practice but somehow we turned it round".
Vettel had surprisingly held the upper hand over Hamilton throughout practice but suffered an issue in the final session and required a new engine.
There were comforting words from Vettel to his mechanics, and he chose to look on the bright side of a complex situation such as saving tires for race day.
"I felt like I made the right decision, but even if I'd stayed ahead I think he would have understood", Hamilton said.
"We need to see now what the problem is but we managed to do the change in time".
"It was a shame that I couldn't get it out".
"If the safety vehicle comes out at a time that suits you, it might bring you back and then you never know what is possible". "But who knows, maybe we're back after a year or two, I don't know".
Back to the race on Sunday, the weather may well play an important part as it did a year ago, when it was won by Daniel Ricciardo in his Red Bull. Nico Rosberg had been on pole position in his Merc.