Yesterday I wrote about why I felt the Cardinals would be making a mistake to trade significant value to bring in a new shortstop. I think some combination of Jedd Gyorko, Aledmys Diaz, and Greg Garcia will be trying at times, but comes at a better value than parting with value elsewhere. While my post dealt mostly with the idea of trading for Erik Aybar from the Braves, yesterday John looked at the cost of acquiring Nick Ahmed from the Diamondbacks, coming to the conclusion that the speculated price tag (Luke Weaver) was too high for a mostly glove only shortstop. I definitely agree, though I would question Gammon's speculation there, as I seriously doubt the Diamondbacks would actually ask for a price even that significant for a player of Ahmed's stature, even purely as a bargaining tactic. For better or worse, the Diamondbacks are the oddballs of the league though, so you never know what they're going to ask for.
Anyways, in my post yesterday I emphasized that I wouldn't mind the Cardinals picking up an extra shortstop on the cheap, to kind of hedge the internal bets of Gyorko/Diaz/Garcia. Around the same time it was reported that Ruben Tejada was placed on waivers by the Met's. The Met's and Tejada already agreed to a $3M deal for Ruben's final year of arbitration, and that's what the Cardinals would be picking up, if they were the only N.L. team to put in a waiver claim (since they had the best record in the NL they get the last shot, but they can beat any A.L. team's claim). That's certainly a small amount of money in baseball terms at this point, but the Cardinals could alternatively bet on no A.L. teams putting in a claim, then negotiating a deal with Tejada for lower than the current $3M price tag.
But, Tejada isn't a great fit really, despite coming at a cheap price. Ideally, any new shortstop would be someone who was a clear upgrade on defense, to at least give the Cardinals flexibility with a late inning defensive replacement, and someone to start the day that say, Jaime Garcia, an extreme ground-ball pitcher, is on the mound. He gets mixed reviews on the eye test and the projections, with UZR considering him a just below average shortstop but with a very badly rated 2015. You could either hand-wave that away as just being an outlier season typical of the high variance that goes with defensive metrics, or you could see it as him trending downward defensively. Really, the truth is almost certainly somewhere in the middle. DRS considers him much worse than UZR, with him at -20 runs on his career, -15 of which came in 2015.
At the plate, Tejada has mostly been a disappointment based on his expectations. Dave Cameron over at Fangraphs yesterday wrote on the inevitability of the Cardinals acquiring Tejada, and within he cited a dangerous looking trend in contact rate. From 2013 to 2015, Tejada's contract rate went from 89% to 83%, to 80%. Those numbers wouldn't look that bad if he was trading K's for power, but Tejada has never had a season with an ISO over .089. He does walk at an above average rate, and even with the contact issues he strikes out less than average, but it's not enough to make up for the lackluster power, and average BABIP skill.
Overall, Tejada has been about as good as the internal options are projected. For his career, Tejada has been worth 1.45 WAR/600 PA, and when averaging both Zips and Steamer projections, he's projected for less than a full win over a full season in 2016.
There's also the matter that, if the Cardinals let Tejada pass through waivers, and Tejada is released, he is likely going to be playing for whomever will offer him the most playing time. The Cardinals are going to want to try out their internal options to see where they're at, and Peralta is still expected to be back by mid-season. The Cardinals would probably like another option, but not someone not clearly better that their internal options that will nevertheless take all the playing time away from those options. It may seem like the shortstop situation is dire, but according to Fangraphs' depth charts, the Cardinals are still projected for 10th best output from the shortstop position. The 2.5 wins at shortstop match the projection for second-base, and is larger than what is projected at first-base and both corner-outfield positions.
At the minuscule prices involved, I certainly wouldn't be upset if the Cardinals took a flyer on Tejada. Not much can go wrong, and it's another option they didn't have before. But it really doesn't seem like a good fit, and frankly I'd rather just see what Gyorko, Diaz, and Garcia can do for a couple of months.