McLaren is still waiting for news from Honda on whether or not Stoffel Vandoorne will escape an engine change penalty at this weekend's Singapore Grand Prix.
The tight-and-twisty Marina Bay circuit offers McLaren one of its best chances of a decent points haul, thanks to its chassis having shown good performance at similar high downforce venues.
But Vandoorne could find his hopes of a top finish dashed early on,if Honda finds that it is not able to repair the MGU-K shaft that broke on his engine in Italy.
The component, which failed in qualifying, could not be changed in time for the race, and then the Belgian was forced out of Sunday's event with a repeat failure.
Although there had been some optimism that Honda would simply be able to fix the problem without the need for a new engine, that has not yet been confirmed by the Japanese manufacturer.
Racing director Eric Boullier said: "Singapore is one of the best chances of the year in terms of matching our package to the characteristics of this gruelling street circuit.
"We've worked hard to try to avoid incurring any penalties which could halt our progress there, and we hope that following Stoffel's retirement in Monza we won't have to use any new power unit elements, although this is yet to be officially confirmed."
Honda introduced a slightly updated power unit at the Italian GP which helped Vandoorne to a slot in Q3, despite Monza's high-speed straights not being ideal for McLaren.
With Singapore's corners a better hunting ground for the team, Boullier is bullish about what to expect at a venue which should be one of the most favourable of the season for it.
"The second best after Budapest," he explained. "In Singapore, it should be both cars in Q3 as a target."