1. Rick Porcello, Starting Pitcher, Detroit Tigers

Porcello had by far the best season of his career last year.  However it is not very likely that he repeats last seasons results.  Porcello had four straight seasons with an ERA above 4.00 before last years breakout season when he posted an ERA of 3.43.  However this year Porcello will be pitching in the much more hitter friendly confides of Fenway Park.  Even if Porcello manages to maintain a sub par ERA he gives up too many hits (over 200 in three out of six seasons played) for it to be much lower than 4.00.

Sure Boston made some improvements this offseason, but they finished in last place last year at 20 games under .500 meaning less wins are likely for Porcello, really putting a damper on his fantasy numbers.  

2. Nelson Cruz, Texas Rangers, Outfield

Last seasons homerun leader, Cruz is likely to go very early in this years drafts.  There are many reasons why would should steer clear of Cruz this season.  For starters he will be 34 next season and even though he finally played a full season, Cruz has dealt with too many hamstring and back issues throughout his career to rely on to play back to back full years.  Besides health concerns last season was only the second time in his career that Cruz has gone over 30 homeruns, and was only the first time with more than 100 RBI.  

Cruz has also benefited much of his career from playing in smaller ballparks between Rangers ballpark in Arlington and Camden Yards.  This year Cruz will batting in Safeco a much bigger ballpark which is going to greatly limit his power numbers.  While his RBI numbers may not take too much of a hit with the improved Mariners lineup the homeruns are sure to drop.    

3. Matt Kemp, San Diego Padres, Outfield

Finally a healthy season from Kemp after back to back injury riddled seasons, Kemp provided his fantasy owners with great offensive numbers.  He batted .287 with 25 homeruns, 89 RBI, and 77 runs while platooning for some of the season.  Kemp was poised to have another big season this year but that was before being traded to the Padres.  Kemp will be moving to one of the biggest ballparks in baseball which is going to limit his power numbers.  That’s not a good sign for a player who already has eliminated the speed side of the game from his fantasy numbers as he only has 26 steals in the last three seasons combined after stealing 40 in 2011.  Kemp will still bat for a good average as he is a career .292 hitter but he will certainly see a drop in the power numbers.  The Padres have made so many trades this season who knows where Kemp will bat in their revamped lineup which is going to have an affect on his total number runs and RBI.  Kemp should still be a decent fantasy play this year but based on how early he is likely to go in this years drafts it would be wise to pass on him.

4. Justin Morneau, Colorado Rockies, First Base 

Morneau rejuvenated himself last season when he batted .319.  Morneau was fairly lucky last season with a BABIP just .011 points higher than his actual batting average.  Morneau also hasn’t been remotely close to a .300 batting average since the last time he batted .300 back in 2010.  Also surprisingly moving to Coors Field did not provide a power increase as he only belted 17 homeruns, the same number that he hit two seasons ago.  At age 34 Morneau is well past his prime and is a huge risk if you are banking him on repeating the high batting average that he hit for last season.  

5. Victor Martinez, Detroit Tigers, Designated Hitter

Improbably at 35years old Martinez posted a career best season last year.  He batted .335, just one percentage point lower than his career best, belted 32 homeruns which is easily a career best, and also drove in 103. Getting up there in age it is highly unlikely that Martinez is able to keep up that type of production.  In all likelihood Martinez will still bat right around the .300 mark but the power numbers are going to fall.  Only six times has Martinez hit 20 or more homeruns in a season and I would not expect next season to be the seventh time.  If you are taking this player in the first five rounds you are buying high off of a career best year at a very late age when many players start to decline.