George Russell has promised to fight back after Mercedes team principal Toto Wolff described the Briton's difficult season as a "catastrophic moment" following teammate Kimi Antonelli's stunning world championship triumph.
Russell, 28, entered the season as the overwhelming favorite for the title, but Antonelli overturned expectations to become the youngest world champion in Formula One history, leaving his more experienced teammate trailing.
The 20-year-old has claimed nine victories to Russell's three, sealing the championship in just his second season with a third-place finish at Sunday's Mexican Grand Prix.
Russell has admitted that the campaign has been the most disappointing of his career, particularly given his expectations of challenging for the title in a season he had identified as a major opportunity.
He graciously congratulated Antonelli in the moments after the race before Mercedes allowed him to leave the circuit without fulfilling his mandatory media duties.
Russell posted on Instagram on Monday, admitting he had found it difficult to keep going this season.
"Now feels like a pretty suitable moment to speak from the heart," he wrote. "This season started off exactly how I had hoped but it very quickly unravelled with tough luck and poor performances.
"It's been the first proper season of my career where I've had more bad days than good. Has it been tough to deal with? Yes, very. Has it been tough to pick myself up week in, week out? Yes, very.
"Confusion at times? Often. All I know is that I've given it my all and 2026 was not meant to be my year.
"I want to sincerely congratulate Kimi on what has been an absolutely incredible season. You truly deserve the championship.
"Now, all I can promise is that for the rest of this season, and into the next one, I will be giving my absolute all to rediscover the performance I have been capable of producing for the majority of my career and fingers crossed a little bit of luck returns."
Mercedes were fined 5,000 euros ($5,610) by the FIA over Russell's failure to attend his post-race media duties.
Wolff explained why he had allowed Russell to leave after seeing how upset he was following the race.
"He's distraught about the situation. It was a great show of sportsmanship to go and see Kimi," Wolff said.
"I have known George for such a long time and I know for a sportsperson, for a racing driver, this is a catastrophic moment.
"I've been in situations where it's very, very difficult to cope. So him not doing the media work or leaving the track is absolutely understandable. Him staying would have actually surprised me."
Russell started Sunday's race from second but was swallowed up by several cars on the run down to Turn 1 as his Mercedes appeared to struggle with power delivery.
He then collided with Red Bull's Isack Hadjar, earning a 10-second penalty, before finishing sixth.
Russell is now fourth in the drivers' championship after being overtaken by Max Verstappen and Lewis Hamilton.
"Maybe the race was a little bit a picture of his season. This was a race for him to win. We had the pace in the car," Wolff added.
"And we let him down on the first straight. The energy delivery is not what we thought it should be. And so I'm very much with him at the moment."