The fact that this has already caused three pages of debate shows that it isn't at all a clear decision. On first sight I was certainly concerned about it being SFP (never really thought it was DOGSO, given distance & proximity) but the replays showing glancing contact below the ankle made me doubt that. That said, if it had been given, I could've seen why.
It is then, to me, a classically 'orange' card. As referees, we also know that you can't combine the 'nearly DOGSO' and 'nearly SFP' to come up with a red. Plenty of players, managers, pundits and fans can do that - but we shouldn't.