Weiss replaces Jim Tracy, who resigned Oct. 7 after the Rockies stumbled to a 64-98 record this season.
The new Colorado manager played 14 major league seasons with Oakland, Florida, Colorado and Atlanta -- putting together a career .258 batting average with 25 home runs in 1,495 games.
Weiss was named rookie of the year in the American League as a member of the Athletics in 1988 and also played in four World Series.
He joined the Colorado front office in 2002 as a special assistant to the general manager.
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