The 29-year-old was replaced after an ineffectual performance in the 62nd minute by Jamie Mackie, who spearheaded an incredible 3-2 comeback by the R's, but Barton's departure was met by cheers from the home faithful, who booed the midfielder off the pitch.
"I was awful," Barton said via his Twitter account. "Worst I've ever played in my career. But we WON.......and that's the most important thing. Onwards and upwards.
"Disappointed with fans booing, were [sic] meant to be in it together. They won't break me, guaranteed. I've been through much worse.
"Enough of the negative anyway. What a result, great spirit shown by the boys and loyal fans tonight. Not the bells that booed."
Barton later posted: "Form is temporary, class is permanent."