clock menu more-arrow no yes mobile

Filed under:

The Trade Deadline Is Terrifying

No, not because of who's running this roster. At least, not only because of who's running this roster.

I don't have much time to come up with a witty intro, so I'll just say this - with the state of the Mariners' current rotation, lately I've been thinking about the history of starting pitcher trades at the deadline. How often do they work? How often do they bomb? We know there's not much out there on the market, but Ho's a guy we badly need to upgrade in the worst way if we don't want to feel like we're punting every fifth game for the rest of the year.

Thanks to the wonder that is Baseball-Reference, I've found out that, over the past decade, more than 70 teams have gone out and acquired an alleged rotation upgrade around deadline time (between July 1 - August 31). 64 starting pitchers who collected at least five starts for each team were involved in those trades, averaging a 93 ERA+ pre-deal and a 105 ERA+ after. Sounds encouraging, right?

On the surface, yeah. But here's the trouble: despite the 12-point average improvement, there's historically been almost no way to accurately predict what you're going to get from each individual pitcher (spreadsheet here). Observe:

(that crazy point at 318 is Randy Johnson in 1998)

An r-squared of .04 is extraordinarily low, indicating an incredibly weak correlation between pre- and post-trade ERA+ values. Put another way, historically speaking, where a guy stood before being dealt told you little about how he'd do afterwards.

The average change in ERA+ was 25; excluding Randy, it's still 22. For the sake of perspective, the difference between Ryan Feierabend and Jeff Weaver this year is 21. The following is a column graph of the distribution:

18 of the 64 pitchers saw their ERA+'s remain fairly stable. However, 20 saw their ERA+'s change by at least 31 points, which is hugely significant. Since 1998, starting pitchers acquired at the deadline have been slightly more likely to perform completely differently than stay around the same level after being traded.

You might say that the overall average pre- and post-trade values of 93 and 105 still suggest that adding a pitcher is a good idea more often than not, but dig a little deeper and even that isn't so clear anymore. Of the 23 pitchers with an ERA+ of 100 or higher at the time of the trade, 14 of them got worse. In other words, among the starters who seemed most likely to stabilize their new rotations, 60% of them failed to meet expectations. The guys who've historically fared the best after being dealt are actually the arms that looked like garbage; the 20 pitchers who were dealt with ERA+'s of 80 or below saw an average improvement of 19 points. That Cory Lidle in 2004 was quite a find.

Maybe there's no better way to look at it than this:

Average Post-Trade ERA+ Of Starters With A Pre-Trade ERA+ Of 100 Or Higher: 114
Average Post-Trade ERA+ Of Starters With A Pre-Trade ERA+ Under 100: 100

But when you exclude the Randy Johnson trade, since that was an anomalous and unique situation:

Average Post-Trade ERA+ Of Starters With A Pre-Trade ERA+ Of 100 Or Higher: 105
Average Post-Trade ERA+ Of Starters With A Pre-Trade ERA+ Under 100: 100

The guys who looked like the biggest upgrades were only 5% better than the second, third, and fourth-tier starters who didn't get nearly as much press or attention. If that isn't a telling statement, I don't know what is.

As Jarrod Washburn has made readily apparent to all of us, starting pitchers are volatile, and when you narrow their window of performance down to two months, it's almost impossible to predict how they're going to do. Of all the non-Randy Johnson starters who've been dealt near the deadline over the past ten years, the biggest upgrade was Woody Williams in 2001, who went 7-1 with a 2.28 ERA in 11 games for St. Louis after leaving San Diego as arguably the worst starter on the team. Meanwhile, the biggest letdowns were Esteban Loaiza and Denny Neagle, who went to New York with solid track records of recent success and promptly bombed. Loaiza cost the Yankees Jose Contreras, who went on to become a good starter in Chicago. Neagle cost the Yankees Ed Yarnall, Jackson Melian, and Drew Henson, three highly-regarded prospects who'd shown up on BA's top-100 lists. Williams cost the Cardinals an old Ray Lankford.

Lots of teams need starting pitching at the trade deadline, but few teams get it, and even fewer manage to land an arm that actually performs how they thought it would. They're unpredictable, and by virtue of this fact alone it's almost always unforgivably short-sighted and ignorant to give away a lot of value for someone you can only hope will help you over the following two months. Forget the big names. Forget the people everyone's talking about, and forget taking part in negotiations with a GM who's holding out for a king's random for one of his starters. Scour the lesser-knowns like JP Howell and Anthony Reyes and try to act surprised when they out-pitch Dontrelle Willis. It may not be as sexy, but chances are in the end you've preserved your resources without taking much of a hit at all in terms of performance.

This may not really apply to the Mariners anymore, since all the rumors seem to have them connected to relievers instead. But even so, pity the next poor bastard who unloads for a big name starter at the deadline. Odds are good that two months later he'll be living a life of regret.