A growing unhappiness in San Francisco has risen all the way to the top.
"Thank you #49ersfaithful for coming out strong tonight," he tweeted. "This performance wasn't acceptable. I apologize for that."
While there is still time to turn things around this season, the tweet will not be taken lightly around the league. Amid a season-long series of reports about York clashing with coach Jim Harbaugh, it's hard not to wonder if the comment was meant to be heard by more than just the fans.
Harbaugh, for his part, said he did not see the post but didn't exactly fight back against his boss' thoughts.
"I thought our guys -- I thought we got, they played better as a team than we did," Harbaugh said when asked if the team's loss was unacceptable.
That stretch will likely define how York truly feels about his team and coach, though he certainly seems to be leaning in one direction at the moment.