The Raiders had four open roster spots heading into their rookie minicamp but they weren't settled on even the players they had signed previous to that and made a lot more moves than was expected.

First off, they signed seven players who had been in rookie camp for tryouts. Those players are CB Chance Casey-Thomas, LB Eric Harper, WR Greg Jenkins, TE Jeron Mastrud, DE Ryan Robinson, C Andrew Robiskie and CB Mitchell White.

In addition to those tryout players, they claimed third year WR Andre Holmes off waivers from the New England Patriots. Holmes was a teammate of Raiders' left tackle Jared Veldheer at Hillsdale college in Michigan.

With eight new players signed, they needed to cut ties with at least four players under contract. They did one better and cut five, including three players who had just been signed as undrafted free agents following the draft.

Those UDFA who had their cup of coffee with the Raiders and were sent home were CB Adrian Bushell, C Deveric Gallington, and LS Adam Steiner. The team also waived DB Akwasi Owusu-Ansah and TE Mickey Shuler.

The waiving of Bushell and Gallington are very much a surprise. Those two were considered among the best UDFA signings of the off-season.

Here are short descriptions of the newly signed players per the Raiders press release:

Chance Casey-Thomas (5-11, 190) CB - Baylor: Started all or parts of four seasons as a safety, playing with Robert Griffin III from 2009-11. Finished with 212 tackles (161 solo), six for loss, three interceptions, 18 passes defensed and three forced fumbles. Also returned punts for the Bears. Eric Harper (6-3, 240) LB - Grambling State: Transferred from Louisiana Tech prior to his senior season, then in his first season as a college starter had 54 tackles and 6½ sacks. Played primarily tight end until his transfer. Lost his house in Hurricane Katrina, which forced him to play for another high school. Greg Jenkins (6-1, 208) WR - Alabama State: Compiled 17 touchdowns and almost 2,200 yards in the Southwest Athletic Conference's most productive offense Jeron Mastrud (6-5, 255) TE - Kansas State: Signed as an undrafted free agent with Tampa Bay in 2010, then spent training camp with the Bucs and the first couple weeks of his rookie season on the Patriots' practice squad, before Miami signed him to its active roster. Played in 36 games with six starts over his first three NFL seasons (2010-12), all with Miami, catching one career pass for 8 yards. He was eligible to participate in the rookie mini-camp despite being fourth-year player because he did not receive a qualifying offer or minimum salary tender from his previous team (Miami) upon expiration of his contract. Ryan Robinson (6-4, 255) DE - Oklahoma State: A junior-college transfer, started his senior year at OSU and finished second on the team with six pass breakups, in addition to 32 total stops (25 solo), 8½ tackles for loss and 2½ sacks. Spent two years at Jones Community College. Father and three uncles played college football. Two of those uncles played for the New York Jets and Washington Redskins, respectively. Andrew Robiskie (6-1, 297) C - Western Illinois: Started the final 25 games of his career on the offensive line, including his senior year exclusively at center. Helped the Leathernecks to a record-setting year and an NCAA playoff berth as a junior in 2011. Son of former NFL RB Terry Robiskie, now the WR coach for the Atlanta Falcons, and brother of the Detroit Lions' Brian Robiskie. Mitchell White (5-11, 184) CB - Michigan State: In 43 college games, finished with 26 career tackles (12 solo) and one pass defensed. Played primarily as a reserve defensive back and special-teams contributor during his four years with the Spartans. A former walk-on, earned a scholarship prior to his sophomore campaign. Also competed as a high-jumper on the Michigan State track team. Identical twin brother, Myles, a WR at Louisiana Tech, signed late last month as a non-drafted free agent with the Green Bay Packers. Waiver claim: Andre Holmes (6-4, 210) WR - Hillsdale: Third-year player was waived by the New England Patriots Friday. Played in seven games with the Dallas Cowboys last season, registering two receptions for 11 yards. Joined the Cowboys as a free agent for the final four games of the 2011 season, but did not see action. Entered the NFL with the Minnesota Vikings as a non-drafted rookie free agent out of Hillsdale, where he was teammates with current Raiders T Jared Veldheer

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