Being said in an insulting context does not solve the issue of whether or not it was a racial slur. If you think it does, please elaborate. As I have said, because it has a positive context it also has an inverted, negative context via sarcasm. Accepting it was an insult simply narrows it down to a negative context,it doesn't specify exactly what the insult was.
To use my earlier example, if I shout at someone and call them a ****, it's clearly in a negative context. However, because there is more than one negative meaning to the word "****", you can't establish whether or not my insult was based around sexual or physical dirtiness. Unless I missed the bit where Suarez points to Evra's skin (which would still be far from conclusive) or makes monkey noises or something equally obvious and repulsive, then you will struggle to narrow down the "context" to a degree where you can assert it was a racial slur.
@Jack Fulham- Down South, Scouser has negative connotations associated with the stereotypical Liverpudlian, it's basically a byword for a thieving, uncouth pisshead. Given that this is the Lpool thread, I'd like to point out that that's not why I think but what the word generally means down.