Chargers defensive end donkey kicks opponent in the stomach and nothing happens

In the second quarter of the Chargers-Raiders game on Sunday, Raiders' Donald Penn shoved Chargers' defensive end Corey Liuget, who then kicked the offensive tackle right in the stomach. Penn then jumped on top of Liuget before the scuffle was broken up.

Refs saw the whole thing but only penalized Penn on the play.

Liuget can probably expect a concerned call from the NFL this week.