* Fox to pay $500 million to $600 million a year-source * Turner to pay between $300 mil to $325 mil a year-source * Deal includes digital rights * Deals boosts league's rights fees by 100 percent By Liana B. Baker Oct 2 (Reuters) - Major League Baseball said it reached an 8-year agreement with Fox Sports and Turner Broadcasting on Tuesday, in a deal a source said was worth up to $7.4 billion. The league and the two broadcast companies did not disclose financial details on Tuesday. The league said in a statement that the two agreements combined with a recent deal with ESPN will boost the league's annual rights fees by 100 percent. News Corp's Fox unit will pay between $500 million and $600 million per year, while Time Warner's Turner cable unit will pay between $300 million and $325 million per year, according to a source familiar with the deal who requested anonymity because the financial terms were confidential. Based on those figures, the combined deal is worth between $6.4 billion on the low end and $7.4 billion on the high end. The deal, which starts in 2014, is a renewal of a previous agreement between the league and the two companies from 2006. As part of the new deal, the World Series and All-Star Game will stay on Fox, while other playoff series will be shared between Fox Sports, TBS and MLB Network, according to a statement. Fox said it would have the rights to broadcast more regular season games on Saturdays. Fox and Turner will receive digital rights to allow viewers to stream games on the Internet if they have a pay-TV subscription. The agreement comes on the heels of Disney-owned ESPN striking an 8-year deal in August that sources said was worth $5.6 billion. That is nearly double what the popular cable network pays now for baseball. Sporting events are among the shrinking number of broadcasts that viewers watch live without skipping commercials, and can command some of the highest rates from advertisers. This has drawn more bidders to sports programming, driving prices higher and providing a boon to sports teams.