MESA, Ariz. -- The Cubs have invited three more players to Spring Training camp, including outfielder Matt Murton, right-handed pitcher Ryan Williams and lefty Edgar Olmos.Including the players previously announced, the Cubs will have 21 non-roster invitees in camp. Pitchers and catchers have their first workout Saturday, and the first

MESA, Ariz. -- The Cubs have invited three more players to Spring Training camp, including outfielder Matt Murton, right-handed pitcher Ryan Williams and lefty Edgar Olmos.

Including the players previously announced, the Cubs will have 21 non-roster invitees in camp. Pitchers and catchers have their first workout Saturday, and the first full-squad workout is scheduled for Feb. 24.

Olmos, 25, was designated for assignment on Friday to make room for lefty C.J. Riefenhauser, who was claimed off waivers from the Orioles. Olmos, who spent most of last season at Triple-A Tacoma in the Mariners' organization, cleared waivers on Tuesday.

Murton, who will wear No. 21, rejoins the Cubs. The 34-year-old was dealt to the team from the Red Sox in the Nomar Garciaparra trade in July 2004, and in four seasons with the Cubs batted .294, hitting 28 home runs with 104 RBIs. He played one season with the Rockies, then spent six seasons with the Hanshin Tigers in Japan.

Williams, 24, was the Cubs' Minor League pitcher of the year in 2015 after posting a 14-3 record and 2.16 ERA in 26 games (24 starts) at Class A South Bend and Double-A Tennessee.

The 21 non-roster invitees in Cubs camp now include 12 pitchers: right-handers Stephen Fife, Brandon Gomes, Jean Machi, Felix Pena, Jonathan Pettibone, Armando Rivero, Drew Rucinski, Duane Underwood Jr. and Williams, and lefties Luis Cruz, Jack Leathersich and Olmos.

There are three infielders (Jesus Guzman, Munenori Kawasaki and Kristopher Negron), four outfielders (Albert Almora, John Andreoli, Juan Perez and Murton) and two catchers (Taylor Davis and Tim Federowicz).

Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast.