The 31-year-old corner started all 16 games for the Steelers last season, compiling seven passes defends, two interceptions and 46 tackles. Pro Football Focus rated Gay their No. 34 corner out of 118 in 2015.
Cornerback is a need position for the Steelers this offseason, in free agency and the draft. Locking down Gay ensures Pittsburgh will have depth at the position and a reliable veteran in event an upgrade can't be attained.
Here are Tuesday's other transactions: