Sammy Solis ( Sammy Solis (

With the midnight deadline looming to set 40-man roster and protect players from the Rule 5 draft, the Nationals added left-handed starter Sammy Solis, right-handed reliever Aaron Barrett and outfielder Michael Taylor to the 40-man roster. In order to make room on the roster, the Nationals designated left-handed relievers Fernando Abad and Tyler Robertson for assignment.

Solis, 25, a second-round pick in 2010, is highly regarded within the Nationals system and pitched well in the Arizona Fall League, posting a 2.17 ERA in 29 innings. This was his first season back from 2012 Tommy John surgery and he punched up a 3.43 ERA in 57 2/3 innings at Class A Potomac. General Manager Mike Rizzo recently suggested that Solis, one of the Nationals’ best starting prospects, could be used as a big league reliever this season.

Taylor, 22, a sixth-round pick in 2009 out of high school in Fort Lauderdale, hit .263/.340/.426 as he repeated Class A Potomac in 2013. He hit 10 homers and 41 doubles, but struck out 131 times and walked only 55 times. He is known, however, as a defensive wizard. Baseball America rated the 6-foot-4, 205-pound player as the best athlete and defensive outfielder in the Nationals’ minor leagues. While his hitting has room to grow, Taylor could be an elite defender in the majors.

Barrett, 25, a ninth-round pick in 2010, punched up a 2.15 ERA and a 1.093 WHIP in 51 appearances at Class AA Harrisburg. He struck out 69 and walked 15, relying on low 90s fastball and slider rated as the best in the system by Baseball America. The Nationals have enough relief pitching on their roster, but they felt Barrett’s potential was enough to protect him from other teams in the Rule 5 draft.

The designation of Abad for assignment is mildly surprising. Abad, 27, who was signed last winter to a minor league deal, was part of the Nationals mid-season bullpen overhaul. He started strong but faded toward the end. He still finished with a 3.35 ERA over 37 2/3 innings. The left-hander struggled against left-handed batters, allowing them to hit .306 off him.

Robertson, 25, was acquired off waivers from the Minnesota Twins in June and remained in the minors all season. He posted a 3.04 ERA in 26 2/3 innings with Class AAA Syracuse. He is the son of Jay Robertson, a special assistant to Rizzo. With all the moves, the Nationals’ 40-man roster is full. The Rule 5 Draft is on Dec. 12.