Desmond Jennings  is struggling to consistently get on base at the top of the Rays lineup and has been for some time. With the Rays looking for every advantage they can to generate runs is it time that Joe Maddon  removes Jennings from the top of the Rays lineup card?
The best leadoff hitters will specialize in getting on base, will possess speed and the smarts to steal bases, and as an added benefit also make the pitcher pay when he makes a mistake. After Jennings made his season debut on July 23rd he posted a slash line (batting average/on-base percentage/slugging percentage) of .259/.356/.449 for the remainder of the season. In addition he stole 20 bases, and hit 10 home runs in 287 plate appearances. For comparison, the AL average slash line for leadoff hitters in 2011 was .265/.326/.395. By all appearances the Rays looked to have that dynamic leadoff hitter that ignites an offense for years to come.
Teammate Sean Rodriguez  knows the value of a great leadoff hitter when he told the Tampa Tribune  “Every great team has a really good leadoff hitter. I don’t care what anyone else in the lineup could be doing, if you don’t have a good leadoff man, those solo homers aren’t going to mean anything.”
Unfortunately, Jennings has not been able to show the growth expected after the 2011 season and since the beginning of the 2012 season he has posted a sub-par slash line of .244/.316/.392. Of the 29 leadoff hitters that have had 250 or more plate appearances since the beginning of the 2012 season his on base percentage ranks 22nd, his batting average ranks 23rd, and his slugging percentage ranks 18th. On the plus side he remains an exceptional base runner and ranks 8th in runs scored and 3rd in stolen bases.
He has struggled thus far this season hitting .236 (19 for 84) and despite having a better than league average walk rate of 9.3% he has an on-base percentage of .289 which of 21 leadoff hitters with 65 or more plate appearances he ranks 17th. He has run into his share of bad luck as it seems that whenever the Rays have had a stellar defensive play made against them the ball was put in playoff his bat. His recent problems (4 for 22 with 11 strikeouts) may be the result of fatigue after starting each and every game this season and why on Friday he was given the night off.
Joe Maddon  knows that Jennings is still in the development stage as a leadoff hitter saying “Desmond has a chance to be a very classic leadoff hitter as he gains more experience, He’s a really good base stealer and the big thing with him is that when he doesn’t expand his strike zone and accepts his walks, that’s when he becomes very dangerous.”
Jennings himself knows the importance of getting on base saying “My job is to get on base, period, I don’t care if it’s a hit or a walk, it counts. For me, it’s all about scoring runs.” The question is whether or not he should continue to hit leadoff when he returns to the Rays lineup or should Maddon take some of the pressure of him and bat him lower in the lineup even if only for a short period of time.
In The Book: Playing the Percentages in Baseball written by Tom Tango, Mitchell Lichtman, and Andrew Dolphin they reach the conclusion that the optimal lineup will feature the teams best hitters batting #1, #2, and #4 with the leadoff hitter emphasizing the ability to draw walks and get on-base and the cleanup hitter with a strong slugging percentage. Since Jennings is struggling to get on-base it would make sense to move him down in the lineup where the Rays could still take advantage of his speed.
The Book suggests that if you need to leverage a base stealer, put him in front of a batter who hits a lot of singles and doesn’t strikeout much. The likelihood is that your base stealer will be batting fifth or sixth. In this context the Rays offense may be best served by positioning Desmond Jennings  5th in the lineup and hitting James Loney  or Kelly Johnson  behind him.