Gausman, 22, was the Orioles' 1st round selection (#4 overall) in the 2012 First Year Player Draft out of Louisiana State University. He is scheduled to make tonight's start in Toronto and will become the third member of his draft class to play in the majors, joining LHP PACO RODRIGUEZ (#82 overall, LAD) and LHP MICHAEL ROTH (#297 overall, LAA). Gausman made eight starts for Double-A Bowie this season, going 2-4 with a 3.11 ERA (46.1IP, 16ER), posting four Quality Starts. He entered the 2013 season as the Orioles' #2 prospect according to both Baseball America (also the #26 overall prospect in baseball) and MLB.com (#36). He will wear #37.
Arrieta, 27, did not pitch after being recalled on May 18. He went 2-1 with a 2.75 ERA (19.2IP, 6ER), 17 strikeouts and three walks in three starts for the Tides after being optioned on April 22. He was 1-1 in four starts with the Orioles earlier this season.
Burnett, 25, has made two appearances for the Orioles, allowing three earned runs in 1.1 innings.