Per league rules, players first signed at age 18 must be added to 40-man rosters within five years or they become eligible to be drafted by other organizations through the Rule 5 process. Players signed at 19 years or older have to be protected within four years.
Washington also designated left-handed pitchers Fernando Abad and Tyler Robertson for assignment.
Fully recovered from Tommy John surgery, the left-handed-throwing Solis recently led the Arizona Fall League in wins (5) and strikeouts (29) en route to a 2.17 ERA in seven starts. Solis, 25, has a career mark of 10-4 with a 3.20 ERA in 33 games spanning three professional seasons. According to MLB.com's Jonathan Mayo, Solis ranks as the 11th-best prospect in the organization.
The Nationals consider him a future starter, but if he makes the team out of Spring Training in 2014, Solis could be considered to serve as one of the lefties out of the bullpen. The Nats are looking for lefty relievers this offseason.
Barrett is a reliever with a fastball clocked as high as 95 mph. His go-to pitch is a slider. Barrett fanned 12.3 batters per nine innings this season for Double-A Harrisburg. Barrett's 26 saves ranked second in both the Eastern League and in Washington's system. He is considered the 16th-best prospect in the system, according to Mayo.
Taylor, 22, could be the team's center fielder of the future, ranking near the top as the best defensive center fielder in the system. This past season, Taylor hit .263 with a career-high 57 extra-base hits (41 doubles, six triples, 10 home runs), 87 RBIs and 51 stolen bases in 133 games with Class A Potomac. He was the Nationals' sixth-round pick in the 2009 First-Year Player Draft. Taylor is currently leading the Puerto Rican Winter League with a 1.042 OPS (.381/.441/.595).
As for Abad, he had a respectable 3.35 ERA in 39 games for the Nats this past season, but he struggled getting left-handed hitters out. In fact, lefty hitters hit .306 against him.
Robertson had a combined four wins, two saves and a 3.04 ERA in 47 Triple-A games spent with Syracuse and Rochester this past season. He was claimed off waivers from the Twins on June 7.
The Nationals have 10 days to trade Abad and Robertson, reassign them to the Minor Leagues, or release them.