The Brazilian was penalized twice in a row for fouls on Daniel Podence and Chiquinho in the second half in some pretty bizarre scenes.
After Oliver played an advantage for the first foul, he produced two yellows seconds apart to condemn Mikel Arteta’s Arsenal to another red card.
Such is the rarity of the decision, the debate is likely to continue as to how strictly the law should be applied.
“I think there’s just a moral issue with what the referee did,” Keown said on BT Sport.
“It doesn’t look sporty. You [to Joleon Lescott] have a different opinion, I haven’t seen it too many times. Maybe that’s going to be a theme, maybe we’re going to see that now all over the country.
“I asked the producers to tell me and there’s really only one or two of those incidents that happened.”