Honda F1 boss Yusuke Hasegawa isn't throwing in the towel but fears he won't be able to convince McLaren not to leave the pair's partnership.
McLaren and Honda are in their third year together but while the Japanese manufacturer has shed its blood, sweat and tears since 2014 it hasn't succeeded in delivering a performing and reliable power unit to the Woking-based outfit.
As a divorce looms, with an announcement expected as soon as this week, Honda has been holding on however, pressing on with upgrades despite its crumbling relationship with McLaren.
"I'm still trying to make good performance to convince them [McLaren] but I'm not sure it will be enough," said Honda chief Yusuke Hasegawa.
"We Honda never give up to keep this collaboration."
Curiously, Hasegawa reveals that Honda difficult state of affairs has boosted its troops, both in Milton Keynes and back in Japan at the company's base at Sakura.
"It's accelerating our development. It becomes motivational inside the factory," said the engineer.
Haseagawa is hoping Singapore - a track better suited to McLaren-Honda - will bring a positive result.
"We have some confidence about competitiveness [at Singapore]," he added.
"We have already decided the current engine will go to Singapore. We may update some settings or engine settings but we cannot do a big update in Singapore."
McLaren took a strategic grid penalty at Monza in order to race with fresh and updated engines in Asia. But it could all turn out to be too little too late for the collapsing partnership.