Frequently compared to Matt Cain due to their similar physical stature, the 6-foot-4, 220-pound Crick finished 3-1 with a 1.57 ERA in 14 starts for Class A San Jose last year. The 21-year-old Crick, who's rated the top prospect in the Giants' organization by MLB.com, proceeded to post an 0-1 record with a 2.87 ERA in seven Arizona Fall League outings with Scottsdale.
Blackburn, ranked second on MLB.com's list of Giants prospects, went 7-5 with a 3.65 ERA for San Jose last season. The 21-year-old also struck out 138 while walking just 35 in 133 innings.
The left-handed Blach was San Jose's leading winner last year, going 12-4 with a 2.90 ERA in 22 games (20 starts). The 23-year-old, MLB.com's No. 11 Giants prospect, issued just 18 walks in 130 1/3 innings while striking out 117.
Though the Giants consider their starting rotation set with Cain, Madison Bumgarner, Tim Hudson, Tim Lincecum and Ryan Vogelsong, the organization expects Crick, Blackburn, Blach and others to begin competing for jobs as early as next season.
Williamson, MLB.com's 16th-ranked Giants prospect who's physically imposing at 6-foot-5 and 240 pounds, led the organization's Minor League system with 25 homers last year while hitting .292 in 136 games. The 23-year-old also struck out 132 times in 520 at-bats.
Other familiar names among the non-roster pitchers invited to camp included right-hander Brett Bochy, manager Bruce Bochy's son; right-hander Jose Casilla, setup reliever Santiago Casilla's younger brother; right-hander Chris Heston, a closely watched prospect last year; right-hander Derek Law, who excelled in the AFL last year (zero earned runs in 12 1/3 innings spanning 11 appearances); right-hander Kameron Loe, who has played for five Major League teams in nine seasons; right-hander Sandy Rosario, who went 3-2 with a 3.02 ERA in 43 games for the Giants a year ago; and left-hander Dan Runzler, who spent parts of the 2009-12 seasons with San Francisco.
The non-roster list features recognizable position players such as catcher Guillermo Quiroz, who hit .186 in 43 games with the Giants last year; infielder Joe Panik and catcher Andrew Susac, San Francisco's top two selections in the 2011 First-Year Player Draft; and Chris Dominguez, who batted .294 with 15 homers in 132 games for Triple-A Fresno last year.
Other non-roster invitees include right-handers Jason Berken, Rafael Dolis, J.C. Gutierrez, Mitch Lively, Adam Reifer and Mason Tobin; catchers Jeff Arnold and Ben Turner; infielders Brandon Hicks and Mark Minicozzi and outfielder Javier Herrera.