The Mariners claimed Gonzalez off waivers and optioned him to Triple-A Tacoma on Tuesday.
The right-hander was designated for assignment by Atlanta over the weekend but will retain a place on a 40-man roster with Seattle. Prior to the transaction, Gonzalez had spent the full season at Triple-A Gwinnett and had a 3.95 ERA, 1.37 WHIP and 39:19 K:BB across 41 innings.