Darnell, 26, hit .246 in 15 games with Triple-A Tucson (Padres) last season before being designated for assignment and released in June. He played primarily in the outfield in 2013, but also appeared at first and third base.
At the time of Darnell's release, the right-handed hitter was sidelined for the remainder of the season with a left shoulder injury. He played in 25 Major League games for the Padres over two seasons (2011-12). In six Minor League seasons, he owns a career .297 average, .394 on-base percentage and .502 slugging percentage.
Garrido, 24, went 0-5 with two saves and a 3.03 ERA in 39 games out of the bullpen for Double-A Northwest Arkansas (Royals) last season. He also made one appearance with Triple-A Omaha in 2013. Over seven seasons in the Royals farm system, the right-hander compiled a career 14-25 record with a 4.37 ERA.
Garrido made the switch to full-time reliever last season.
Olmedo, 32, has spent parts of six seasons in the Major Leagues and has played 15 seasons professionally. The switch-hitting shortstop spent all of last season with Triple-A Rochester (Twins). He hit .234 in 105 games with Rochester, appearing at second base, shortstop and third base in addition to one relief appearance on the mound.
Olmedo has compiled a .230 batting average in the Major Leagues while spending time with the Reds (2003-06), Blue Jays (2007) and White Sox (2012). He has a .262 average in the Minors over 1,423 games. This marks Olmedo's third stint in the Rays organization as he spent the 2009 and '11 seasons with Triple-A Durham.
Solis, 26, hit .179 between Double-A Altoona and Triple-A Indianapolis last season in the Pirates organization. Prior to 2013, the right-handed hitting Solis spent seven seasons the Padres organization, earning a five-game stint in the Major Leagues in 2012. Solis has thrown out 34 percent of attempted basestealers while playing in the Minor Leagues.
Bill Chastain is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.