John Hart stepped down Tuesday as general manager of the Texas Rangers, clearing the way for 28-year-old Jon Daniels to become the youngest GM in major league history. Hart's resignation came two days after the Rangers finished 79-83, their third losing season in four years under Hart and their fifth since winning their last AL West title in 1999. Hart, whose teams won six division titles in his last seven years in Cleveland ending in 2001, will be replaced by Daniels, who at 28 years, 41 days, is about 10 months younger than Theo Epstein was when he became Boston's GM on Nov. 25, 2002. Daniels was promoted from assistant GM and Hart will remain a team consultant. "He's got a truly brilliant mind, he's a walking baseball encyclopedia," Texas owner Tom Hicks said of Daniels. "I think his youth is an asset to us. ... I did my first leveraged buyout when I was about that age. Young people can kind of do things in this life."