He was irate after the game and complained of having double vision in his left eye from what he called a "dirty" shot delivered by Jeremy Newberry.
Barnett claimed that Newberry intentionally poked him in the eye as the first half was winding down.
The incident occurred away from a downfield pass completion by the Raiders that had ended.
"We were talking, he lines his (index) finger up, and he poked me in my eye, and he's got nothing to say," said Barnett, who suffered a scratched cornea. "I'm figuring he's just pointing at me, talking to me, but I'm like, 'Uh, oh, he really pointed at me because he struck me in my eye.'"
Barnett walked off the field and had to go to the locker room before halftime for evaluation. He was cleared to resume playing at the start of the second half, wearing a protective visor on his facemask. The confrontation between Newberry and Barnett didn't result in a penalty.
Packers coach Mike McCarthy said he wasn't privy to any visual evidence of the poke in the eye, so taking the incident up with the league might not happen.
Barnett was to see an eye doctor for further examination Monday, but the team doctors don't consider the injury to be serious.
Barnett, who had a game-high 10 tackles, didn't go out of his way to retaliate against Newberry or any other Raider in the second half. Nor did Barnett hunt down Newberry on the field when the game ended.
"I'm not talking to that guy," Barnett said. "I'm not accepting no apology for that right now. Not at this moment because it's just dirty. That's just one of those NFL codes where you don't poke somebody in the eye and you don't spit in someone's face."