Olbermann will host TBS' Major League Baseball postseason studio show, joining analyst and Hall of Famer Dennis Eckersly.
In other TBS sports news, Ron Darling, who joined TBS as an MLB anaylst in 2008, has reached a long-term extension with Turner Sports. And Hall of Famer Cal Ripken Jr. will transition from the studio to the broadcast booth full time in the postseason.
Ripken, who had primarily served as a studio analyst for the last six years, will join play-by-play announcer Ernie Johnson and and Darling as a three-man commentator team throughout the 2013 postseason.
In a conference call, Olbermann called his new job a perfect fit.
"Baseball is my passion ... on a professional level, this is great for me because it's what I do. I did this at home to the TV by myself. Now there will be people watching. I'll get paid for it and I get to wear a tie rather than sitting around in a uniform pretending to be a player."
When asked if he would stick with sports or get back into politics, Olbermann said, "The last time I sat at a telephone news conference to announce I was leaving politics to go to a baseball pregame show and sports in general in 1999, it was the first time I ever said I have absolutely no idea where my career is going. I have certainly learned not to make any predictions."
He added, "This is my focus. The opportunity to do this was so compelling that I agreed to it and we [had] never discussed if I was getting paid. This is it. I have been so bad at predicting my own career future, as everybody else has, that it would be useless. This is what I'm doing and I can't wait to get started."
A release by TBS highlights his status as a "noted baseball enthusiast" and his previous sports broadcasting experience, including anchoring ESPN's "Sportscenter" from 1992 to 1997. Most recently, he served as a guest host for MLB Network's "Hot Stove."
"It's well known that Keith is a fan of the game, and when you combine that with his studio experience, keen insight and passion for baseball and its history, he'll add a new dimension to our MLB postseason studio shows," said David Levy, president of sales, distribution and sports for TBS.
Said Levy, "We're excited to have him join Dennis in studio, and look forward to Keith sharing his in-depth knowledge for the game, MLB teams and players with our viewers for three great weeks in October."
The release did not mention Olbermann's stormy stint at Al Gore's Current TV last year, where he had hosted "Countdown." Sources said his bosses had grown frustrated after Olbermann took repeated unexcused absences from "Countdown," including the night before the March 6 Super Tuesday primaries.
He had previously hosted "Countdown" at MSNBC, but abruptly left in 2011 after clashes with his bosses.