Rizzo hadn't played since April 5, and he wasn't in the lineup for Monday's scheduled, game which was postponed because of weather. The move will be retroactive to Friday, which means Rizzo would be eligible to be activated prior to next Monday's game against the Cardinals. This would mark Rizzo's first career trip to the DL.
In Rizzo's absence, backup catcher Victor Caratini had been filling in at first base. Ben Zobrist and Tommy La Stella are also capable of manning the position, as is Efren Navarro. Of course, none of the above is as good of an option as Rizzo himself. Navarro, who gets the call here, is a career .243/.306/.334 hitter.
Rizzo, perhaps because of these back issues, had been off to a slow start in this, his age-28 campaign. On the young season he's batting just .107/.219/.214 with one home run, albeit across a sample of just 32 plate appearances. Rizzo's a three-time All-Star who should still be in his prime, and he's core member of the reigning NL Central champs. Once he gets healthy, he should start producing in a customary manner.