Adding a veteran ace to the rotation will likely help the St. Louis Cardinals in the near term and hinder them in the long run

On Wednesday I looked at why it makes sense for the St. Louis Cardinals to upgrade their rotation with a top-tier starter. What planted the seed for that post was St. Louis Post-Dispatch columnist Bernie Miklasz's post on the Cardinals' reported interest in adding David Price, Cole Hamels, or Max Scherzer in which Miklasz opined that such an addition could help the Cardinals strengthen their roster for "the long haul." The crux of my Wednesday post was that such a strengthening the starting rotation would be about attempting to best the Pittsburgh Pirates for the Central crown in 2015, not fend of the Cubs over the long term.

Miklasz reached out via Twitter with a good question:

@b_g_h Ben, liked your piece (as always) but have to ask: doesn't motivation to sign ace cover both goals? Win now + strengthen long term?

— Bernie Miklasz (@miklasz) January 14, 2015

I replied on Twitter, but that medium isn't necessarily the best for such a discussion. Consequently, I wanted to reiterate some of my points (since not everyone is on Twitter) and also expand on them this morning—especially since I didn't clearly communicate my thoughts on this in yesterday's post.

First, I want to frame the discussion. We often throw around terms like "win now," "short term," and "long term" when talking about baseball personnel moves. However, we don't often define what those terms mean to us. Personally, I have always thought of "near term" or "short term" to be the next one or two years. "Medium term" covers three to four years. "Long term" is five years and beyond.

The reasoning behind my definitions is that five years in baseball is a rather long time. Think back to the 2010 Cardinals. It feels like aons ago. In baseball time, it was.

Furthermore, players are under club control for six or seven years and there aren't all that many free-agent contracts that are signed for over five years. So, to me, five-plus years is the long haul or long-term planning in baseball.

These definitions in part underly my belief that adding any of the big names the Cards are rumored to have interest in is a move to improve the club for the long term. Consider the players' respective ages and contract statuses:

• Price is entering his age-29 season and is under club control for 2015 only.
• Hamels is entering his age-31 season with four years remaining on his contract at a $94 million salary (and an option for a fifth year).
• Scherzer will likely sign a six- or seven-year deal worth around $200 million. His age-30 season will be the first of that contract.
• James Shields will play his age-33 season in the first year of his free-agent contract, which is shaping up to be four or five years in length and $90 to $100 million in value.

At Fangraphs a few years back, Bill Petti and Jeff Zimmerman collaborated on some very interesting posts on pitcher aging. Petti's posts have some very informative charts that illustrate the aging curve for a wide array of pitcher stats, including a lot of peripherals not often explored in such studies. The posts are well worth reading in their entirety. From Petti and Zimmerman's introductory post, here's the methodology:

The same method was used as the one that Jeff previously used to calculate hitter aging curves (all the heavy math is in the linked article). To get the aging amount, Jeff took each of the pitcher’s rates in one year and compared them to how they did the next year. Each pitcher’s change was then weighted by the harmonic mean of the number of innings they pitched between the two seasons. Finally, all the weighted values are added together to get the total amount of change for each metric. Note that the curves are cumulative: For example, when it comes to fastball velocity, pitchers lose a total of 3.75 mph on average during their careers.

I'm not the kind of guy who will attempt to get you to read a post (or multiple posts) by simply quoting their methodology. I'll also give you a taste of their handsome graphs. Here's the graph for starting pitchers from the first post:

Eno Sarris summed up their findings pretty well in a Sports on Earth article that is also worth reading:

Here's a nasty open secret about pitching: Young pitchers don't get better as they age. There is no peak age. As soon as they start firing bullets they start running out of time. They're born and then they start dying.

Overall, it's true: K/9 drops with age; velocity tumbles dramatically; BB/9 goes up; BABIP and HR/9 rise; and FIP goes up. As a group, starters start aging young and don't age particularly well.

In December, Miklasz's Post-Dispatch colleague and Best Podcast in Baseball co-host Derrick Goold reported on the Cardinals being linked to Scherzer. In the article, Goold quotes general manager John Mozeliak about long-term pitching contracts in general:

"Just to start to chase something because we feel we have some bandwidth with payroll I think only makes sense if you truly feel you have a need," Mozeliak said. "At this point, we feel the guys we’re running out in the rotation are pretty good. In terms of going out and making that large investment those out (future) years end up being more painful than the first couple. That’s what we’re trying to avoid."

This is why I believe the Cardinals' reported interest in Jon Lester, Hamels, Price, and Scherzer is more about winning in the near term than the long term. Petti and Zimmerman's graphs regarding overall starter aging trends bolster Mozeliak's assessment (which itself is likely informed by a similar analysis) that the out years of long-term pitcher contracts are "more painful than the first couple." By the time the Cubs emerge as a force to be reckoned with in the NL Central, there's a good chance that any veteran ace the Cardinals might add for 2015 and beyond will be a hindrance to the club's pennant pursuits because of age-induced decline and a rather high salary.