When the Ravens play the Houston Texans on Sunday, they'll be using their third different long snapper of the season.
The team signed Patrick Scales on Thursday and placed Kevin McDermott (elbow) on injured reserve. McDermott had originally beaten out Scales when the Ravens had a tryout to replace veteran long snapper Morgan Cox, who tore his anterior cruciate ligament on Oct.19 against the Atlanta Falcons.
McDermott snapped in seven games for the Ravens and was mostly solid. However, a high snap last week against the Jacksonville Jaguars contributed to Justin Tucker missing a 54-yard field goal.
The Ravens are plenty familiar with Scales. He was with them during the 2011 and 2012 training camps, and coach John Harbaugh said that he performed well during the tryout with the team in October.
"Patrick is a guy that was with us in training camp twice who we have a lot of respect for, as well," Harbaugh said after McDermott was signed. "Both of those guys had excellent workouts and we feel like either one of those guys would fit us really well."
Scales has been on four teams, but he's never snapped in a regular-season NFL game.
McDermott becomes the 17th Raven this season to go on season-ending injury reserve. That's the most since they had 19 players on IR in 2008.
The Ravens also announced that they have added running back Tauren Poole to their practice squad and released tight end Emmanuel Ogbuehi.
Poole, who played his college ball at Tennessee, has spent time with the Carolina Panthers, Indianapolis Colts, Pittsburgh Steelers and New Orleans Saints. He played one game with the Panthers and fumbled on his only carry.