A transition duct used in a gas turbine engine to direct the hot gas flow from the combustor into the turbine section of the gas turbine engine. The transition duct includes a plurality of guide vane integral with the duct. The transition duct includes a circular shaped inlet end for connection to a can combustor and a rectangular and arched shaped outlet end for connection to a first stage turbine section. the guide vanes extend within the flow path between inner and outer projections each having a curved opening in the shape of the airfoil each airfoil includes inner and outer airfoil ends with retainer slots formed between the airfoil ends and the duct projections that form shear pin retainer slots. Shear pin retainers are secured within the slots to secure the guide vanes to the duct in a thermally uncoupled manner to reduce thermal stresses. The guide vanes can be made from a single crystal material for higher gas flow temperatures.