If he doesn’t make that trade, we may not finish over .500. I’m serious. We were hurting.

- Tony LaRussa

On July 27th, the day that the St. Louis Cardinals traded center fielder Colby Rasmus, Trever Miller, Brian Tallet and P.J. Walters to the Toronto Blue Jays for Edwin Jackson, Octavio Dotel, Marc Rzepczynski and Corey Patterson, the eventual winner of the National League Wild Card was six games above .500, half a game back of the Milwaukee Brewers for first place in the NL Central and 5.5 games back of the Atlanta Braves for the Wild Card.

After acquiring Jackson, Dotel, Rzepczynski and Patterson, the Cardinals played better than .600 baseball in the final 58 games of the regular season, largely because of a remarkable 18-8 record in September. They went on to overtake the slumping Braves on the final day by beating the Houston Astros as Atlanta fell to the Philadelphia Phillies. The Cardinals’ improbable run continued through the playoffs. First, they beat the heavily favoured Phillies in the NLDS, and then the team conquered the Central Division rivals, the Milwaukee Brewers, bringing them to the 2011 World Series.

There’s an old joke about causation that goes something like this:

A scientist has a frog that is capable of jumping whenever it hears a voice command telling it to do so. The scientist is rather intrigued by this, so he decides to experiment a little bit. First, he slices off the frog’s hind leg and says, “Jump!” Sure enough, despite the missing appendage, the frog jumps. The scientist then slices off another limb, and commands it to jump. The frog does so again. Then, the scientist cuts off another extremity, says “Jump!” and once again, the frog complies. Finally, the scientist slices off the frog’s last leg and requests that it jump one more time. When the frog is unresponsive, the scientist concludes that removing the limbs of a frog causes it to go deaf.

You see, just because the results indicate that the team played better after new players arrived, it doesn’t necessarily mean that those players caused a transformation. Let’s take a deeper look at the specific impact of each player that came over in the deal for Colby Rasmus.

We can start by looking at their contributions in terms of playing time and wins above replacement according to FanGraphs after arriving in St. Louis.

  • Edwin Jackson: 12 GS, 77 IP, 0.7 fWAR
  • Marc Rzepczynski: 28 GP, 22.2 IP, 0.4 fWAR
  • Octavio Dotel: 29 GP, 24.2 IP, 0.9 fWAR
  • Corey Patterson: 44 GP, 56 PA, -0.3 fWAR

We could also look at where each player ranks on the team in terms of fWAR during the final month of the season. For instance, out of position players with 10 or more plate appearances in September, Patterson ranked 16th out of 17. Out of pitchers with more than one start in the month, Jackson ranked fourth out of five. And out of relievers who made more than a single appearance in September, Dotel ranks first and Rzepczynski ranks fourth out of seven.

Aside from Dotel, it appears that the additions all had an average or below average contribution, and this is perhaps best reflected in the total win probability that each player added during his time in St. Louis.

  • Octavio Dotel: +0.21
  • Edwin Jackson: -0.23
  • Marc Rzepczynski: -0.42
  • Corey Patterson: -0.49

This means that three of the four players acquired from Toronto did more to decrease the probability of St. Louis losing than winning. Going even further, we see that of the 31 games that Patterson made an impact in his team’s WPA, it was negative 24 times and positive seven times. Over his 12 starts, Jackson had a positive WPA impact on the six times and a negative one six times as well. Meanwhile, Rzepczynski’s appearances resulted in one neutral, 17 positive and 10 negative WPAs. However, when he was called in with the highest leverage situations, Rzepczynski was ultimately disappointing collecting four shutdowns, but also five meltdowns for the Cardinals.

For more on shutdowns and meltdowns, read here.

Once again, the only clearly positive contribution was from Dotel who in addition to collecting seven shutdowns to four meltdowns, had 21 positive WPA outings to only six negatives (and two neutrals). Anyone who followed the Toronto Blue Jays in the second half of the season probably doesn’t have to look up the numbers to know how Dotel’s contribution compares with Colby Rasmus. It’s not pretty. The center fielder struggled after coming to Toronto, which isn’t to say that we know this outcome would be the same if he were to have spent the entire season in St. Louis.

Considering that three of the four players acquired by the Cardinals in the trade will either be free agents this off season or at least would have been had they not been traded (Dotel has a team option for 2012 with a 40% pay increase), and the one who is under team control will in all likelihood end up a reliever, it’s difficult to see them winning this deal in the long term.

However, this was done for the sake of the short term. The Cardinals, perhaps enjoying the last year of Albert Pujols on their team, went for an all or nothing approach. So, for the sake of argument, let’s assume that acquiring Dotel led to more wins for the team than if they had hung on to Rasmus. The pre deadline deal becomes a bit of a win-win for both teams involved, right?

Not quite. If Octavio Dotel is the difference maker in the trade, it becomes difficult to overlook the fact that any team in baseball could have acquired the veteran reliever this past off season without risking the loss of a player who could potentially be one of the top young center fielders in the game. Praising Cardinals GM John Mozeliak for his trade deadline dealing is to undervalue foresight and completely dismiss what other teams were doing around the same time.

Consider that general manager Jon Daniels acquired Mike Adams, Mike Gonzalez and the surprisingly disappointing Koji Uehara for Chris Davis (stalled prospect), Tommy Hunter (future bullpen arm at best), Robbie Erlin (a legitimate prospect) and Joe Wieland (low ceiling prospect). The difference between Daniels’ dealings and Mozeliak’s become even more lopsided when you consider that Adams and Uehara are both under team control next year.

And this is what I see as the major difference between the two clubs squaring off in the baseball finals. One is a smartly built, dynamic and well rounded team that boasts a superior rotation, bullpen, lineup and bench. The other has gotten to where they are by luck, while being praised for their ultimately faulty design.