If you are in a keeper league, chances are that your league’s trade deadline is quickly approaching. July 31 and August 1 are popular dates for some leagues. Some AL- and NL-only leagues push the deadline back a little later to allow for players traded from the “other” league to be included in deadline deals. In some keeper leagues, the trade deadline is as late as August 31.

By now, most teams that have given up on 2013 have packed it in already. The trades these teams are making now are primarily focused on fine-tuning their rosters. Much of this fine-tuning comes in the form of adding minor league picks or players for veterans in the last year of their fantasy contracts (available in the draft/auction next year). Some owners might try to swap a categorical excess for a deficiency.

One thing that most fantasy owners neglect to do is look at what the value of a player will be in the context of inflation at next year’s auction. Many fantasy owners simply take an approach where they do the following:

  • Target young talent that is undervalued and/or potentially undervalued next year
  • Jettison high-priced players off of their roster regardless of what those players will earn next year
  • Ignore boring “par” players who won’t form the core of a future contender but will “move the chains” and push a team toward a title

It certainly is important to target young talent and build your core around players like this. However, you do not want to overdo it. Owners who built around Oscar Taveras and Billy Hamilton this year expecting significant contributions were probably rebuilding at some point in June. This isn’t to say that you want to avoid young players. The converse is true. Good young players are the keys to the kingdom. If you speculated on Jean Segura last year and kept him this year, more power to you. Young emerging players should be the foundation of your rebuilding effort.

However, where I think fantasy owners often get lost in the weeds is in ignoring core players who are at a par price but produce $25 or more of stats and complementary players who don’t have the allure of a Taveras but will earn $10-15 consistently year in and year out.

Even more so than the examples above, where owners really get lost is in failing to factor in auction inflation into their value calculations. This ties into the established philosophy I mention above, and compounds the failure of a good fantasy owner to rebuild his team and plan for the following season.

Here’s an example of this type of scenario playing out. You’re out of the running for this year. The only good players you have left on your AL-only squad are Robinson Cano at $35 and Prince Fielder at $34. An owner who is going for it offers you Justin Smoak at $11. Should you make the deal?

Much of this calculation obviously depends upon where you have Cano, Fielder, and Smoak valued. But for the sake of argument, let us assume that you have Cano valued at $33, Fielder at $31, and Smoak at $15. At face value, it seems obvious that you should make the trade. Cano is two dollars overvalued, Fielder is three dollars overvalued, and Smoak is four dollars undervalued. It appears that you are gaining nine dollars of auction value by making this trade. Get Smoak!

Lost in this analysis is that there will be inflation at your auction next year. What does inflation do to Cano, Fielder, and Smoak’s respective values?

Table 1: Trade Analysis: Robinson Cano and Prince Fielder for Justin Smoak


+/- Cano

+/- Fielder

+/- Smoak






Smoak +9.00





Smoak +3.73





Cano/Fielder +0.67





Cano/Fielder +4.38

In a league with no auction inflation, Smoak provides much more value than Cano and Fielder. But look at what inflation does to the value in this trade! With a light amount of auction inflation (10 percent), the deal for Smoak is still worth making. Push the inflation to 20 percent, and now you’re looking a virtual push. With 30 percent inflation, even though Smoak is a raw bargain and Cano and Fielder are slightly overvalued, now you don’t want to make this trade. Cano and Fielder are more valuable to your roster than Smoak in 2014.

This is the hard math behind auction keeper leagues. If you trade away Fielder and Cano for Smoak, even though you’re getting value back in Smoak you still need to spend that extra $58. At auction, a $30 player with 10 percent inflation will cost $33. In an auction with 20 percent inflation, that guy now costs $36. When you trade away your high priced players, you’re not only trading away their value but you’re trading away those dollars as well.

A team with nothing but a host of $5-10 freezes will typically have $180-200 to spend in an auction with a $260 bid limit. It’s hard enough to avoid overpaying in an inflation auction with $140-160 left to spend. With all that cash, it is pretty much impossible. There’s nothing wrong with trying to get undervalued players when you’re dumping. Don’t forget, though, that you need stats as well. Trading big-ticket items is fine if you’re dumping and the situation calls for it, but it shouldn’t be your default position.

Thank you for reading

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I've often thought about this same conundrum and it manifests itself more and more the deeper into a league one gets as there seem to be more bargains that are kept from the previous year.

What is the best way people have found to account for inflation? I've found in the past that a best fit exponential trendline in excel has worked to calculate average auction values and then one can use historical prices in your league (or similar leagues) to calculate inflation that year and estimate what it might be in future years.

What's interesting in a league that I play in is that there is severe pitcher inflation and not much hitter inflation. Any other calculation variations? Would love to hear how you calculate inflation, Mike.
There isn't really a "best" way to account for inflation, which is what makes keeper leagues so interesting. Even in a start-over auction, each player purchase changes the dynamic of the auction. This phenomenon is even more dramatic in keeper formats.

Historical data can probably be used to gauge whether owners prefer going full bore on top tier players or if they redistribute inflation money to other players.

This is an interesting thing to examine for a future piece. Thanks for the suggestions.
Hi Mike,
My league allows trading future draft pick positions. How do we value those when trading. ie how would you value a trade proposal like 2014 X rounder for Player X?

Thanks in advance
Draft picks in a straight draft or minor league picks in a Roto style league?