Schwartz, who had started all 11 games, broke his left leg Sunday in Washington.
Gettis was with the Giants in training camp and did two stints on their practice squad this season. He was signed to the Raiders practice squad on Nov. 17.
This is the second straight season Schwartz has finished on injured reserve. He broke his left ankle in a game at Jacksonville.
Gettis played 13 games for the Redskins in 2013. He was on the Giants' roster late in the 2014 season, but was inactive for the final two games.
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