The unanimous decision made at today's owners' meeting came two days after Selig and union head Donald Fehr testified before a congressional committee that both criticized baseball for its steroids problem and praised it for strides made the past two years.

Selig will become baseball's second-longest-serving leader behind Kenesaw Mountain Landis, who was the first commissioner from 1920-44. Selig had said repeatedly since December 2006 that he intended to retire after the 2009 season, but many in baseball didn't believe him.

He became acting commissioner in September 1992, when clubs forced out Fay Vincent. After saying he wouldn't take the job, Selig was elected to a five-year term as permanent commissioner in 1998 and gave up running the Milwaukee Brewers, the team he bought in 1970 and his family sold in 2005.

Owners voted in November 2001 to extend his term through 2006, then voted in August 2004 to extend it through 2009. He will be 78 by the end of the latest extension.