Keeper leagues offer up a unique opportunity to buy and sell players, even when games are still a few months away. This guide is designed to help you pick out some trade targets at each position who may have a perceived value in your league that is less than their actual value. The guide also offers players to sell; these players have market values that are higher than their actual value, and you may be able to improve your team by trading them away.

In this installment, I will take a look at the relief pitcher position to identify some good buying and selling opportunities for fantasy owners in keeper leagues. As a reference, you may want to see where these players rank in my Early 2012 Keeper Rankings for Relief Pitchers.

Buys:

1. Kenley Jansen - Los Angeles Dodgers: Jansen has skills comparable to Craig Kimbrel; his 16.1 strikeout rate was beyond outstanding, and his 4.4 walk rate is fine with that kind of strikeout ability. Though Jansen is by far the best pitcher in the Dodger bullpen, Javy Guerra was successful in 2011 in the closer role, so Jansen is likely to start the year pitching the 8th inning. It is highly likely that Jansen will assume the role at some point during the season, and at the point he would have Craig Kimbrel-like upside. It may be better to pay now, because you may not get him later.

2. Sergio Santos - Toronto Blue Jays: Santos fared very well in his first opportunity in the closer role, finishing 2011 with a 13.1 strikeout rate and 30 saves. His SwStr% increased by 3% (to 14%), validating the large jump in his strikeout rate. The move to Toronto will give Santos some tougher competition in the AL east, but should Santos struggle, the other bullpen options that Toronto has are not overly threatening, and though Francisco Cordero has plenty of experience as a closer, his 5.4 strikeout rate from 2011 and 4.00+ xFIP in each of the last three years suggests that his days as a closer should be done. Santos is under club control until 2017, so if he succeeds, he has the potential to keep the job for a long time. If his owner in your league is sleeping on him, or if they fear the presence of Cordero more than they should, try and pick Santos up for what could be a bargain.

3. Vinnie Pestano - Cleveland Indians: With a 12.1 strikeout rate and 3.5 walk rate, Pestano displayed elite skills in 2011. His 2.32 ERA was a bit low, but all of his ERA indicators confirm that his skills are worthy of a sub-3.00 ERA. Pestano is not the closer in Cleveland, but he is the best pitcher in their bullpen and could be in line for saves if Chris Perez (listed below as a sell) struggles early in 2012. Pestano has top-10 closer upside should he get the job.

Additional player to consider buying: Jason Motte and Grant Balfour, both should have the job to begin 2012, both have top-10 closer upside, but neither will be valued that way. Addison Reed, a trendy sleeper for many, but still could be worth a speculative pick up if the cost is minimal. Rex Brothers, could be the closer of the future in Colorado, worth a look in deeper leagues.

Sells:

1. Chris Perez - Cleveland Indians: Perez was very fortunate in 2011 to finish with respectable surface stats and to finish as the closer in Cleveland. His strikeout rate has drastically declined in each of the past two years from 10.7 K/9 in 2009, to 8.7 in 2010, all the way down to 5.9 in 2011, all while maintaining a walk rate of around 4.0. His .234 hit rate was extremely lucky, especially since he gave up a 21% line drive rate. His HR/FB rate has also been a bit lucky at just under 6% each of the past two years, and if that number bumps up closer to the 9.5% league average, his 50% fly ball rate (from 2011) would severely hurt him. Should Perez struggle, Vinnie Pestano, a much better pitcher could take the closer role in Cleveland and run away with it. Perez has been extremely lucky over the past two seasons, are you going to push your luck and hope for a third?

2. Jose Valverde - Detroit Tigers: He converted 49 saves in 49 opportunities in 2011, but he shouldn't be valued as such. Valverde's strikeout rate has dropped in five straight seasons and he produced the worst xFIP of his career in 2011 at 4.01. I do think his job security is pretty strong heading into 2012 since he did convert on all of his opportunities in 2011, but his decline in skills might make him a risk at some point if he begins to blow saves at a rate more appropriate for his skill level. An additional worry is his contract that expires at the end of the 2012 season, making his long-term role more uncertain. Valverde is not a must sell, but the perception could be that he is a top tier closer due to the "perfect season" narrative, if a league-mate has this misconception then you've found your trade partner.

Additional players to consider selling: Javy Guerra, don't think he will fetch much, but he is a closer who is likely to lose his job to the more talented Kenley Jansen at some point in 2012. Brian Wilson, a 5.1 walk rate in 2011, a huge drop in strikeout rate, a slight decline in velocity, a sharp decline in SwStr%, and the depth of the Giants bullpen make him riskier than some may think, good, yes, but no longer elite. Mariano Rivera, if you care about anything past 2012 and can get a respectable return. Joakim Soria, I like his ERA and WHIP to bounce back, but his contract status makes him a potential trade target at the deadline and his long-term role is in question if his club options aren't picked up. Huston Street, the Padres will likely look to deal him at the deadline and he could end up setting for a contending team down the stretch, and like Soria he may not sign as a closer heading into 2013.

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