Flynn was brought onto the Raiders' roster during the off-season with a view to become the franchise's number one quarterback, but Terrelle Pryor won that job during pre-season training camp.
The 28-year-old was given a chance to shine when he was named in the starting lineup to face the Washington Redskins last weekend due to an injury to Pryor, but he was sacked seven times, fumbled the ball twice and threw an interception that was returned for a Redskins touchdown.
"Listen, it is what it is. It hasn't worked out like we anticipated and we've got to make decisions and we've got to move forward and continue to go and [Flynn is] going to continue to battle and scratch and claw and I still believe that he's a capable quarterback but we're going to give McGloin a chance," Raiders coach Dennis Allen told reporters.
"I like what [McGloin] brings to the table, as far as his competitiveness. He's got some moxie to him. He's just understands how to play the game. And I don't think it's too big for him.
"I think he'll come in, if he's called upon, to run the offence [and] I think he'll do a good job. He's smart, he throws an accurate ball, he's got good arm strength, he's good in decision-making. So I like what this kid has to work with."
Flynn has previously played for the Green Bay Packers and the Seattle Seahawks, throwing for a franchise-record 480 yards and six touchdowns in his final game for the Packers.