Olbermann will appear on the show alongside analyst Dennis Eckersley, starting in October, the entertainment industry trade newspaper said.
"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," David Levy, president of sales, distribution and sports at Turner Broadcasting, said in a statement. "We're excited to have him join Dennis in studio, and look forward to Keith sharing his in-depth knowledge of the game, MLB teams and players with our viewers for three great weeks in October."
Olbermann last year filed a breach-of-contract lawsuit against Current TV, accusing his former employer of firing him without cause.
Current TV co-founders Al Gore and Joel Hyatt countered Olbermann was frequently absent from work at his "Countdown" show, refused to promote other Current shows and no longer reflected the values on which the network was established. The matter has since been settled, but the terms were not disclosed to the media.