You would think the easy pick would be Eminem or early '90s era Kid Rock. Because I enjoyed the poll on Gossip Sports so much, I'm not going to fault them for such an obvious oversight, but the site says the Tigers are like pioneer LL Cool J.
"Decent skill, big budget, but still impossible to be taken seriously."

Since Marshall Mathers couldn't rep Detroit, they picked him to be most relevant to the Boston Red Sox:
"Disproportionate percentage of female and white fans. Extremely loud and overbearing, but often with skills and budget to match. Was, at one point, the most outsized and recognizable face in the industry, now settling uneasily back into past-its-prime adequacy."
Jay-Z was, of course, the Yankees.
They went through the entire MLB, division by division with intimate knowledge of the rap industry. Here's what they said about division rival Cleveland, which was compared to Cypress Hill:
"Stormed the scene in the early-to-mid-90s with manic, fast energy and quality skills. Since then has vanished in a cloud of smoke."
I'd say the list is pretty humorous and not completely far-fetched. Worth a read if you have the time.