Promising right-hander Josh Staumont, the Royals' No. 10 prospect according to MLBPipeline.com, and first baseman Ryan O'Hearn, the No. 7 prospect, also received invitations.
Sanchez, 34, had a 7.76 ERA with the Royals in 2012 before being traded to the Rockies that July. He has not pitched in the Major Leagues since his '13 season with the Pirates.
Alburquerque, 30, pitched for the Tigers from 2011-15. His best season came in '14, when he had a 2.51 ERA in 72 games. He pitched two games for the Angels in '16.
League, 33, had 37 saves for the Mariners in 2011 but has not pitched in the Major Leagues since '14, when he had a 2.57 ERA for the Dodgers in 63 games.
Parnell, 32, had 22 saves and a 2.16 ERA for the Mets in 2013. He appeared in six games for the Tigers in '16 and had a 6.75 ERA.
Withrow, 27, was the Dodgers' first-round pick in the 2007 Draft. He had a 3.58 ERA for the Braves this past season in 46 games.
The other invitees included left-handed pitchers Jonathan Dziedzic (13th round, 2013), Eric Skoglund (third round, '14) and Eric Stout (13th round, '14); right-handed pitchers Malcom Culver (eighth round, '08), Luke Farrell (sixth round, '13), and A.J. Puckett (second round, '16); catchers Zane Evans (fourth round, '13), Xavier Fernandez (11th round, '13), Parker Morin (14th round, '12) and Chase Vallot (Competitive Balance Round, '14); infielder Corey Toups (15th round, '14) and outfielder Alfredo Escalera (eighth round, '12). Right-handed pitcher Yender Caramo and infielder Humberto Arteaga both signed as non-drafted free agents and got invites as well.
The first workout for pitchers and catchers will be on Feb. 14, and the first full-team workout is slated for Feb. 17.