Lewis Hamilton posted a message to his fans on social media in which he admitted that last Sunday's Austrian Grand Prix had felt like he was "hanging off a cliff".
The Mercedes driver has been only as good as his car this season, and the Brackley squad's W14 has so far been a mixed bag in terms of its pace and consistency.
The upgrade package introduced in Monaco has inched Mercedes forward, but overall its car's performance remains largely track dependent.
Hamilton and teammate George Russell displayed strong pace in Montreal, with the former finishing third at the Circuit Gilles Villeneuve while the latter was sidelined in the race by a brake issue.
But in Spielberg, Hamilton struggled not only with his car's behaviour but also with his own frustrations.
The seven-time world champion was heard frequently complaining on the radio about his machine's pace, while he also took aim at his rivals' track limit transgressions.
Eventually, team boss Toto felt compelled to intervene, the Mercedes boss twice urging his driver to keep his head down and make the most of the situation.
"Lewis, the car is bad, we know. Please drive it," he said on his second intervention.
©Mercedes
Hamilton concluded his day P7 on the road, but was demoted to P8 following the stewards' post-race bundle of track limit sanctions.
The 38-year-old was visibly unhappy with his Austrian weekend, but vowed to fight on, starting next weekend at his home race at Silverstone.
"There are days when I can say I’m truly proud of myself and days like today when frustration takes over," he confessed on Instagram.
"In a race it can feel like you’re hanging off a cliff and losing the strength to hold on. "It’s confusing for us to have such strong performances one day and then be nowhere the next.
"But when you really care about what you’re doing you brush it off and keep fighting! Heads down for Silverstone, hope to see you all at home."
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