I'm sure you've seen the replays of Seattle Mariners manager John McLaren's post-game press conference last night.
Though rarely talked about unless something like this happens, they're a difficult but integral part of a coach's job. For competitive people who are used to success, after a loss (or a series of losses), a lot of emotions are close to the surface, especially just a few minutes after leaving the field or court. Say what you will about Coach McLaren's press conference, but it's clear he has a passion for winning. Fans appreciate that, I think.
I've had to bite my tongue a few times to keep from letting my emotions spill over. Typically, I'd try to stick with a statistical anaylsis and keep as much emotion out of the interview room as a could. Even then, it's hard to hide emotions.
Still, right before going into the post-game meeting with the press, I'd try my best to compose myself, think about what to focus on, and stay on-message. I assure you, after a loss, it's harder than it looks.