Quiroz, 30, hit .240 with five home runs and 44 RBIs in 250 at-bats for Tucson.
The Venezuelan was in the Mariners system in 2006 and 2009-10. He made brief Major League appearances in all three of those seasons, playing a combined seven games for Seattle while batting .261 (6-for-23) with two RBIs.
His most extensive big league experience came in '08 with the Orioles, when he played 56 games, batting .187 with two home runs and 14 RBIs. He's also spent time with the Blue Jays, and has a career .208 batting average in 101 games.
Patterson, 32, pitched four games in the Majors in 2008 with the Yankees and Padres, posting a 1.93 ERA (one run in 4 2/3 innings). He was waived by the Yankees after one game, then pitched three more with San Diego that season.
The 6-foot-7, 235-pound Pennsylvania native has been with the Mariners in their Minor League system the past two years, going 3-3 with a 3.99 ERA in 36 relief appearances (47 1/3 innings) last year for Triple-A Tacoma and 1-1 with a 2.53 ERA in 16 games (21 1/3 innings) with Double-A Jackson.
In 2010 he was 1-2 with a 2.67 ERA in 29 games (33 2/3 innings) with Tacoma.