The Mariners Thursday selected left-handed pitcher David Rollins, a 24-year-old minor leaguer, from the Houston Astros in the major league phase of the Rule 5 draft. Rollins was the 12th player taken. His addition makes full the club’s 40-man roster.

Rollins, 24, spent last season with AA Corpus Christi. He went 3-4 with a 3.81 ERA (33 ER, 78.0 IP) with 77 strikeouts in 27 appearances, including 12 starts.

In parts of four minor league seasons, Rollins is 23-16 with a 3.39 ERA (135 ER, 358.2 IP) with 343 strikeouts in 88 games, including 64 starts. During his minor league career, he has averaged 8.6 strikeouts per nine innings.

Rollins was signed by the Toronto Blue Jays after being selected in the 24^th round of the 2011 amateur draft out of San Jacinto College (Houston). The lefty was drafted twice by the Mariners, in the 23rd round in 2009 draft and in the 46^th round in 2010.

Toronto traded Rollins to Houston as part of a 10-player trade that saw current Mariners left-hander J.A. Happ go from Houston to the Blue Jays.                      

A player selected via Rule 5 must be kept on the 25-man roster of the drafting team for the entirety of the following season, and the selected player must remain active (not on the disabled list) for a minimum of 90 days. If the player does not remain on the major league roster, he is offered back to the team from which he was selected.