Three things to watch: Bears at Raiders

Three keys for the Oakland Raiders in their home preseason game against Chicago on Friday. Kickoff is set for 10 p.m. ET:

Hayden's debut: Rookie cornerback D.J. Hayden is set to play for the first time since November when he had to have life-threatening heart surgery after taking a hit in practice. He was the No. 12 overall pick in the draft and is expected to be a huge cog for Oakland.

Offensive line: The line is in shambles and it was awful at New Orleans last week. Starter Matt Flynn was sacked four times in the first half. The line has to protect better against the Bears.

Pass-rush: The Oakland's pass rush was a problem last season and it hasn’t shown up yet this preseason. Oakland has to get some production here.