Heath Bell: 2011 Cause for Concern

The new look Miami Marlins went into the offseason pledging to be big players in the free agent market. In what is already old news, they got off to a quick start by signing closer Heath Bell to a three-year deal worth $27M per year. The deal also includes a vesting option for a fourth year at $9M.

As mentioned by Michael in an earlier story on the Bell signing, Bell experienced a drop in performance in 2011. Are those numbers, while certainly not encouraging, a real cause for concern going forward for the Marlins and their new closer? Lets take a look at his numbers, both over his career and his down 2011 season, and use them to see what can be expected of Bell over the life of his contract.

First, lets look at his numbers during his time in San Diego from 2007 through 2011:

Looking at these numbers the K/9 and K% show the most dramatic declines from 2010 to 2011. While the drop in K% is dramatic it must be taken with a grain of salt. The 30 percent he put up in 2010 was outstanding. In a down year in that category in 2011, his 19.9 percent was still in line with a league average reliever, who would expect to have a K% around 19 percent. With this in mind his drop off, while discouraging, is still a respectable number.

Along with the lower K%, Bell also lowered his BB% from one year to the next. His 8.2 percent was the lowest he put up since becoming a full-time closer and is more than one percent lower than league average for a relief pitcher, which is 9.5 percent.

In a similar vein, the K/9 ratio of 11.06 put up by Bell in 2010 was among the best in the league and, therefore, a regression from such an outstanding number was to be expected. Even though his 7.32 K/9 was much lower than his previous numbers in that category it was still slightly above league average.

All of these numbers point out that a down year for Bell is still a league average year.

But the Marlins did not shell out big cash on Bell for league average numbers. They are clearly hoping for a return to numbers similar to those he put up prior to his down 2011 campaign. The question is, what is the likelihood of a return to his previous form? Michael has a great analysis for possible reasons, including the drop in strikeout rate and how the plate discipline against had changed, for the down year Bell experienced in 2011. This post is highly recommended, so I won't go into much detail here. You should check out that post on your own.

Another possible factor in analyzing Bell's numbers that needs to be taken into account is the advantage he gained by having Petco Park as his home ballpark.

I would like to address this assumed advantage of pitching in Petco Park, regarded as a pitcher's park. The dimensions of the new park for the Marlins lend me to believe that it too will be a pitchers park. Chris Towers produced a great overlay comparing both parks. For the sake of comparison, lets look at the park factors of Petco, curtesy of Stat Corner (numbers above 100 favor batters; numbers below 100 favor pitchers):

These numbers show us what we already know, that Petco clearly favors pitchers. It is impossible to get an accurate portrayal of how the new Miami park will play until we get some actual data to work with. Team executives are on record hoping the new ballpark will favor pitchers. Suffice to say that preliminary indications all lend themselves to the ballpark being pitcher friendly, comparable to Petco, mitigating the "Petco Effect" on Bell's numbers.

Next, lets look at the home/road splits for Bell during his time in San Diego:

The number that really stands out when comparing his home/road splits for his four years pitching in Petco is the BABIP, which is 36 points higher on the road than at home. This would explain the higher ERA he posted on the road. League average BABIP is around .300, which is the exact number Bell put up in 174 road innings between 2007-2011. His .264 BABIP at home during the same stretch is a great number. Regression toward average, however, is not necessarily to be expected due to its volatile nature because of its dependence on defense and luck. If the new Marlins ballpark is the pitching haven it seems like it will be we can expect similar numbers from Bell, a good sign for the Marlins and their fans.

Assuming a similar run environment will exist in Miami that did in San Diego, Bell's home numbers are indeed strong and deserving of the big money contract the Marlins gave him. The road numbers should not be expected to be as good as those in Petco when they are compared with one another. Taking this into consideration, the road numbers put up by Bell over the past four years are still good. When looking at the home and road splits in this manner the "Petco Effect," while it cannot be ignored, is perhaps not as dramatic of a concern as feared.

Another tool for projecting the numbers we can expect Bell to produce over the life of his contract comes from using similarity scores from baseball-reference. Lets take a look at the most similar relievers from their age 34 season and see how they continued to produce through their next four years. Here is how the three most similar pitchers to Bell through their age 33 seasons, who also pitched at least four years after turning 34, fared:

Looking at these three comparisons should bring smiles to the faces of Marlins fans. While saves are overrated and not the most telling or reliable of stats, closers are, nonetheless, paid to convert them, and Bell is being paid handsomely to do just that. If he can manage to stay healthy the aging curve for similar relievers has a promising track record. From their age 34-37 seasons Hernandez and Henke were well above league average as noted by their ERA+, 100 being league average. The other comp, Worrell was voted to the All-Star team in 1995 and 1996, even receiving Cy Young and MVP votes, for whatever they are worth, in 1996. Time will tell but let's hope this positive trend continues for Bell and the Marlins.

Taking into account the pitcher friendly environment of Petco, and potentially the new ballpark in Miami, the home/road split, and the success of similar relievers in the past, the future bodes well for Bell and the Marlins.