Abstract: A control mechanism for a combine harvester is disclosed wherein the engagement and disengagement of both the main drive and the auxiliary drive reversing mechanism can be controlled from a single lever. The control lever is pivotally mounted for rotational movement about a pair of perpendicularly disposed pivot axes, one of the pivot axes being rotatable about the other axis. A pair of clutch dogs corresponding respectively to the main drive and drive reverser are engageable with the control lever and separated by a plate-like barrier to prevent a disengagement of one clutch dog and the engagement of the other clutch dog except when the control lever is in a position to effect disengagement of both drive mechanisms. An overcenter linkage is provided with the drive reverser clutch dog to hold the control lever in an engaged position without further input from the operator.