He fumed to The Sun: "The replays show there was nothing.
Ron went for butting Pompey's Richard Hughes.
But the Portugal star said: "I was pushed in the area.
"He came straight to me, put his hand on my neck and I opened my arms in a 'that's enough' way. We pushed each other but nothing serious.
"We leaned heads against each other but that was all. Absolutely nothing else happened.
"I don't know what the ref could have seen to send me off, as you can't even call it aggression.
"When I saw the red card, I couldn't believe it, the situation was so surreal.
"And it's absurd because I'm aware that now I'll sit out a ban for something I didn't do. I feel dejected and very sad."