The term sleeper is overused and commonly confused in fantasy sports. Too many people confuse the concept of a player being undervalued (i.e. a player getting drafted in the seventh round that is going to return fifth round value) versus a player being a true sleeper.
When I think sleeper, I think Rip Van Winkle. I think of somebody that has been off the radar (or maybe has never been on the radar) for so long that people aren't even thinking about them. When talking about sleepers, especially deep sleepers in league specific fantasy setups, we are looking for players that will be drafted in the very late rounds of your fantasy drafts.
The following three players have the opportunity to add value to your fantasy team in the late rounds and have the potential to breakout and be a main cog that helps carry you to a fantasy league championship.
Drew Stubbs - OF, Colorado Rockies
Stubbs' talent, mainly his power-speed combination, has always tempted fantasy owners. Well, what better place for that talent to manifest itself than in the hitter-friendly Coors Field. Coors is the number one hitter's park in the MLB and also ranks number one for home run hitting. Stubbs has a 20/20 season on his resume. He has a 40 steal season on his resume. Last year in Colorado he hit a career best .289. So why is Stubbs' stock not higher? Stubbs is the fourth outfielder in Colorado and has three very good players ahead of him on the depth chart (Carlos Gonzalez, Charlie Blackmon, Corey Dickerson).
Luckily, Stubbs isn't just your typical fourth outfielder. He can play all three positions and you may have noticed that the often injured Carlos Gonzalez is ahead of him on the depth chart. Worst case scenario, Stubbs duplicates last season's numbers, hitting 15 HR, adding 20 SB and providing an average that won't hurt your team total. However, if one of the three starting outfielders goes down for an extended period of time, Stubbs could seamlessly step in and produce a 20 HR, 25 SB season which is great value for a late round OF pick.
Francisco Cervelli - C, Pittsburgh Pirates
As with many of these deep sleepers, opportunity and situation sometimes matter just as much as talent. Cervelli finally finds himself with a serious starting opportunity as he has moved to the NL and joined the Pittsburgh Pirates. With Russel Martin departing Pittsburgh for Toronto, Cervelli becomes the de-facto starter. Cervelli is a solid defensive catcher, something the Pirates are going to want as they continue to develop their young staff.
He's never received 300 AB in a single season, but as long as he can stay healthy, Cervelli could be in line for 400+ AB this season, something that is very rare for a catcher being ranked outside of the top-10 NL backstops. He won't provide much power, but Cervelli is capable of hitting for a high average in the .275-.285 range. If you're looking for a backup catcher, or playing in a two catcher NL only league, make sure to keep Cervelli in mind as a cheap option.
Peter O'Brien - C, Arizona Dbacks
O'Brien is your deepest sleeper of this bunch, as he is currently in the minor leagues. The Diamondbacks reassigned O'Brien to the minors after giving him a serious look in spring training and thinking of him as the possible catcher of the future. While not making the big league team, mostly because of throwing issues behind the plate, is not encouraging, the Diamondbacks remain open to O'Brien being behind the plate in the future while also giving him some time in the outfield at the minor league level. O'Brien is raw, but he also possesses plus raw power that resulted in 34 HR last season across multiple minor league levels.
With the possibility of playing the OF now, O'Brien could possess an Evan Gattis like value where he qualifies at catcher, but gets some time in the outfield keeping him in the lineup on a regular basis and helping that HR total grow. This is a true longshot, but if there is an extra roster spot on your fantasy squad this year, it may be wise to roster O'Brien in the last round of your draft and trying to get some cheap power out of your catcher spot when he is brought up to the big leagues.