Sensabaugh was a free agent who was released by the Los Angeles Rams on Saturday, and Skinner was signed off the practice squad.
To make room on the roster, the Giants released defensive tackle Montori Hughes and rookie cornerback Michael Hunter.
Sensabaugh played in the first three games for the Rams, starting the first two at right cornerback.
In four-plus seasons, Sensabaugh has played in 62 games with 29 starts. He has 176 tackles (141 solo), two interceptions, including one returned for a touchdown, a sack, a forced fumble and three fumble recoveries.
Skinner was originally signed to the Giants' practice squad on Sept. 13. He entered the NFL as a rookie free agent with New England in 2014.
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