McCoil was originally signed by the Chargers as an undrafted free agent in January of 2016. He appeared in two games for Los Angeles this season and made one tackle on special teams. As a rookie last season, McCoil appeared in 16 games with two starts and had 24 tackles, five passes defensed, and one interception.
Jerome joined the 49ers as an undrafted rookie free agent out of Saint Francis (PA) University on May 4. This season, he appeared in four games and had three tackles.
Due to injuries on defense, Jerome played 20 snaps against the Indianapolis Colts on Sunday.
In June, 49ers general manager John Lynch compared Jerome to former NFL defensive back Ronde Barber.
"I played with Ronde Barber and the ball always just found him," Lynch said. "What you realize after a while, it's not finding him. He's finding it and some people say, 'They're just lucky. every tip comes to them.' But that's the way he's been out here (for Jerome).
"I think he led our team during the OTAs and all that in interceptions. And so a guy who's done it in college, albeit at a smaller level, did it in the All-Star games and then he comes out here and it's still happening."