McLaren thinks it cannot afford any more reliability issues this year if it is going to win the world championship.
But despite recent strong pace shown by McLaren, the retirements that Hamilton and Jenson Button have suffered in the last two races have highlighted problems that the outfit needs to overcome.
Nevertheless, team principal Martin Whitmarsh feels it can still give Hamilton the car he needs to triumph, as long as its works hard to ensure there are no more race retirements.
"We have got a reasonably fast car but I would rather no DNFs for the rest of the season," he said. "That would be quite a good way of attacking the rest of this championship.
"We have to make sure that we get Lewis to the finish six more times this year without issues, and if he is doing that and, with the current pace of the car, then the title is possible."
Hamilton's retirement from the lead in Singapore could not have come at a worse time, with the title battle finely poised and the Briton pondering his future options.
Whitmarsh thinks, however, that Hamilton will remain fully focused on pushing on for the title rather than dwelling about what went wrong.
"Lewis has been very strong about it, and he has been supportive of the team," he said. "We are obviously disappointed, but he is in a very strong place.
"We have six rounds of this championship left and there are 150 points available to him; so if we can go out there and win him 150 points then that makes a world championship threat.
"We have to look forward. We are disappointed with the outcome here, but we are not giving up and neither will he. We will keep on fighting."