The last time the St. Louis Cardinals snagged a former Chicago Cubs shortstop, they won the World Series. It is what it is. Rumor has it they're interested in another one for 2013: Former top prospect Ronny Cedeno, who's settled in as a shortstop-of-last-resort all over the National League. Does that mean he's what the Cardinals need to slot between Rafael Furcal and Pete Kozma? Probably not—but like most free agent decisions at this low level, it depends.
Cedeno's been a sub-replacement-level player over his career. He's a below-average hitter—.247/.290/.357—with below-average baserunning and below-average defense. In his two worst seasons—2006, his lone full season as a starter, and 2009—he's cost his team more than a win compared to a replacement-level shortstop.
Since 2009, though, Cedeno's offense has gone from spectacularly bad—.240/.280/.346 for an OPS+ of 61, where 100 is average—to just mediocre—.254/.301/.370, an OPS+ of 85. The difference is mostly BAbip; before 2009, his career batting average on balls in play was .285, and after it's been .313.
Assuming a league-average BAbip around .300, then, it might be that Ronny Cedeno is not one of the worst hitters in baseball. If his new, mediocre bat is a permanent addition, he might even be useful. But it would be a missed opportunity if he's the best the Cardinals can do behind a starter as fragile as Rafael Furcal.