Perhaps this is a Captain Obvious assessment from SI.com's Jon Heyman, but Jim Leyland tops his lists of managers on the hot seat.  We probably already knew that, since Leyland didn't get the contract extension he was looking for.  But maybe even asking for the extension in the first place is what really chapped Dave Dombrowski.  That seems to be Heyman's take:

Leyland's request for an extension even surprised some folks within the Tigers organization, coming as it did after such a debacle. With that disaster fresh in everyone's mind, and a year to go on his deal, Leyland knows the score. The pressure's on him. And that's OK by him.

I was ready to disagree with Heyman, thinking Joe Girardi had to be under more pressure than any other manager, because of what the Yankees spent this winter.  (And he's second on Heyman's list.)  But even though their ownership is much more impatient, the AL East is going to be tough, and maybe that gives Girardi a one-year grace period and the fire would really be cranked up next year.  (I can almost hear Yankees fans laughing at this.) 

However, it seems pretty simple, in Leyland's case.  If they run off to a good start, maybe the team will give him that extension during the season and turn down the heat on that seat.  But if the Tigers stink this year, he won't be back.  Period.