Asomugha played the first two series and was flagged for illegal contact on Drew Brees' 40-yard touchdown throw to Devery Henderson but did not return after that.
According to head coach Tom Cable, Asomugha suffered a left wrist chip fracture that the team believes isn't serious.
"Actually it didn't sound like he would miss much of anything," Cable said. "It's not that big a deal given where it's at and all of that."
Asomugha, who is normally one of the most quoted Oakland players after games, wasn't available and his stall was cleaned out long before the media was allowed into the Raiders locker room.
If Cable is correct and Asomugha's injury isn't serious, Oakland is still likely to hold the veteran cornerback out of the preseason finale against Seattle next week as a precaution.
Asomugha has been battling shoulder and heel pains throughout training camp.
Asomugha injured in preseason loss to Saints
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