The decision to part ways with Romero, who was signed to a one-year, $750,000 contract over the winter, was prompted both by his recent struggles and the team's need to get a fresh arm in a bullpen that just covered 14 innings in a three-game series. Right-hander Eduardo Sanchez took Romero's spot in the 'pen, and he threw a scoreless inning against Chicago.
"He's a lefty specialist that came in and was having trouble getting lefties at times," manager Mike Matheny said of Romero. "It got to a point where we felt we needed to do something."
After beginning the year with eight straight scoreless appearances, Romero struggled mightily in his last three. In a combined 3 1/3 innings, he allowed nine earned runs on 10 hits. The early success came predominately when he was used exclusively to get left-handed hitters out.
Romero, 35, has now been released in-season five times since 2007.
While clubs often prioritize keeping at least two left-handers in the bullpen, the need to meet a quota diminishes when a team has right-handed pitchers who are just as effective getting lefties out. The Cardinals believe that have two such pitchers in Victor Marte and Kyle McClellan.
Marte, who faced two lefties on Monday, has limited left-handed hitters to three hits in 21 at-bats this season. McClellan has held left-handed batters to a .179 batting average in 2012, well under the .210 career average they have against him.
"It's not just somebody that throws with the left hand," Matheny noted. "It's how they pitch to left-handed hitters."
Rzepczynski will continue to be used in late-inning, setup situations, both against right-handers and left-handers. Matheny also left open the possibility of calling upon him earlier in games if a particular matchup necessitates such a move.