Andy Dirks is not in the starting lineup tonight. This is not a surprise, since the California / Anaheim / Los Angeles / Orange County Angels are starting lefty C.J. Wilson. Jim Leyland has typically used a platoon in left field this year with lefties Dirks and Kelly starting against righties, and righties Tuiasosopo and Garcia starting against lefties.
But Leyland does not bench Prince Fielder against lefties, which makes sense. Prince has a career .810 OPS against lefties, better than other options. Incidentally, Victor Martinez has a career .837 OPS against lefties, higher than Prince's.
Does Dirks deserve to have limited playing time with a platoon? Well the sample size is small, but for his career he actually hits lefties a little better with a .340 on base percentage and a .439 slugging percentage. Those numbers are .328 and .425 versus righties. There is some small sample size weirdness, for instance only one double in 158 plate appearances but seven homeruns.
It is hard to rationalize platooning Dirks based on his splits. Dirks is likely a better offensive force against a lefty than is Avisail Garcia, until Garcia has some more experience. If Leyland justifies it based on Dirks being a "dirt bag" and needing occasional days off to avoid the disabled list, then I can handle it. If he argues that he can't have Garcia up with the big league team unless he gets regular at bats, ok. But if he is asked after the game and says "Dirks is a career 0 for 7 versus Wilson", I may come unglued.