One facet that I highlighted in my NLCS preview at Baseball Prospectus was the vulnerability of the Mets’ two big sluggers, Carlos Beltran and Carlos Delgado, to lefthanded pitching. Last night, with Jeff Weaver beginning to falter in the sixth inning, I figured Tony La Russa would call the number of either Tyler Johnson or Randy Flores, his two southpaws. Neither of them is any great shakes, but combined with Weaver’s track record of being tattooed by both sluggers and the fact that he was around 100 pitches, the move seemed academic.

But La Russa left Weaver in to face Beltran, and Beltran jacked a two-run homer for the game’s only scoring. On the whole it was a tight game with good plays and other strategic decisions that could have negated the impact of Beltran’s home run. One can certainly argue that neither Johnson nor Flores is a very experienced, top-flight reliever, that Weaver was in a groove and hadn’t allowed much in the way of hard-hit balls, hadn’t reached 100 pitches, and had handled both Beltran and Delgado before. The non-move wasn’t indefensible, and it’s not as though the rest of the game didn’t have moments that merit scrutiny.

But since I’d keyed on that particular set of matchups, I did find the decision somewhat out of character. I was surprised enough about this sequence of events to bang out a quick piece for BP, trying to understand La Russa’s thought process and showing how just about every piece of matchup data favored him making the call to the bullpen. Here’s a taste:

We spend a lot of time around these parts preaching the gospel of avoiding slavish devotion to LOOGY matchups mainly because they often involve the deployment of an organization’s 14th- or 15th-best pitcher in a high-leverage situation; it’s more constructive to take your chances with a better pitcher regardless of handedness, even on a staff as relatively threadbare as the Cards’ is. Weaver’s been on a roll for the last six weeks–3.22 ERA in 44.2 innings coming into that frame–enough of a roll that you probably have to credit Cardinal pitching coach Dave Duncan for helping him make adjustments and regain some of his former confidence. But Weaver simply doesn’t have a track record of success against the Mets’ two most dangerous hitters.

Meanwhile, La Russa appears to have lost some confidence in his southpaws because they contributed their share of gasoline to the near-massive flameout of September. Flores was dinged for seven runs in 5.1 innings of September action, retiring just 16 out of 30 batters–he was scored upon in five of his last eight appearances. Johnson’s also been shaky, charged with four runs in 6.1 September innings; though he retired 19 out of 26 hitters, he surrendered a pair of homers and took the loss in both of those games amid the seven-game losing streak that put the noose around the Cardinals’ neck.

Still, like every other Cardinal, the southpaws got a new lease on life in the Division Series against the Padres; La Russa called their number a combined total of six times in the four games, and though both pitchers occasionally hiccuped, as a unit the Cardinal bullpen did the job.

The piece hasn’t been up an hour and it’s already burning up my inbox. This should be fun.