The Diamondbacks have acquired left-handed reliever Mike Zagurski from the Phillies in exchange for a player to be named, Zagurski's agent tells Matt Gelb of the Philadelphia Inquirer (Twitter link). Arizona announced it designated reliever Esmerling Vasquez for assignment in a corresponding 40-man-roster move.
Zagurski, 28, was among three players whom the Phillies designated for assignment last week. The southpaw pitched to a 2.65 ERA in 54 1/3 innings with Triple-A Lehigh Valley this season but has struggled in 37 career big league outings, posting a 6.82 ERA in parts of three seasons. His 10.2 K/9 rate is promising, but he struggles with his control (5.4 BB/9).
Arizona's magic number number to clinch the NL West is down to 1, but Zagurski, who will be added to the active roster for the regular season's balance, will not be eligible for the postseason roster.
Vasquez, 27, has posted a 4.66 ERA in 141 career Major League games, spanning parts of three seasons with Arizona. The Dominican right-hander was signed as an international free agent in 2003.
The Diamondbacks' active roster is currently at 33 after the moves. The 40-man roster is full.