That number of veteran free agents figures to grow before camp opens with pitchers and catchers reporting on Feb. 12 and position players on Feb. 17. But the Minor League invitations have now been extended, with Taylor among 10 rookies who'll receive their first exposure to the big league camp.
Also getting their first Major League camp invites are catcher Mike Dowd, infielders Ty Kelly, Gabriel Noriega and Nate Tenbrink, left-handed pitchers Roenis Elias, James Gillheeny and Nick Hill, and right-handers Stephen Kohlscheen and Dominic Leone.
Five other invited Minor Leaguers will be getting their second big league camp experience -- catcher John Hicks and right-handed pitchers Jonathan Arias, Andrew Carraway, Chance Ruffin and Carson Smith.
Taylor, ranked fifth on the Mariners' Top 20 prospect list by MLB.com, is a 23-year-old shortstop who hit .314 with 100 runs, 28 doubles, 11 triples, eight home runs, 60 RBIs and 38 stolen bases in 134 games between Double-A Jackson and Class A Advanced High Desert last year. He was Seattle's fifth-round Draft pick out of Virginia in 2012.
Smith, the Mariners' No. 13-ranked prospect by MLB.com, was the organization's Minor League Relief Pitcher of the Year in 2013 after recording 15 saves and a 1.80 ERA in 44 appearances with Jackson. He and Leone are both hard-throwing right-handers who'll be given a chance to compete for bullpen roles.
Kohlscheen, 25, is a 45th-round Draft pick out of Auburn University in 2010 who emerged last year with a 7-3 record and 2.30 ERA in 41 appearances for Jackson. The 6-foot-6 right-hander led all Southern League relievers in strikeouts per nine innings (11.48) as he struck out 85 batters in 66 2/3 innings with 25 walks.
Kelly, 25, was acquired in a trade with the Orioles for outfielder Eric Thames last June and hit .320 with a .456 on-base percentage in 54 games for Triple-A Tacoma as a middle infielder.
Several of Seattle's top-rated prospects are already on the 40-man roster and thus will automatically be at Major League camp, including No. 1 prospect Taijuan Walker, who'll be competing for a rotation berth as a 21-year-old right-hander.
Other top-ranked prospects already on the 40-man are left-hander James Paxton (No. 6) and outfielders Stefen Romero (No. 7), Julio Morban (No. 11) and Xavier Avery (No. 17). Southpaw Danny Hultzen (No. 2) will miss the entire season after undergoing rotator cuff surgery on his left shoulder, while the other top young prospects will be part of the Minor League camp that opens later in February in Peoria.