The Kansas City Royals claimed Conner Greene off waivers from the St. Louis Cardinals and designated fellow right-hander Burch Smith for assignment on Monday.
The 23-year-old Greene spent last season at Double-A Springfield and Triple-A Memphis, going 4-5 with a 4.09 ERA in 40 appearances. He also made nine relief appearances for Surprise in the Arizona Fall League, where the Royals got a close look at him.
Smith was acquired during last year's winter meeting Rule 5 draft. He went 1-6 with a 6.92 ERA in 38 games for Kansas City, making six starts in spot duty last season.