In a conventional secondary fuel nozzle for a gas turbine combustion system, secondary air enters and flows around pegs to mix with fuel injected through holes in pegs. Because the pegs are in the air flow area, undesirable pressure drops occur adversely affecting turbine's efficiency and leading to higher emissions. A novel secondary fuel nozzle is provided in which fuel is injected upstream of the secondary air entry location, which allows the pegs to be removed from the flow area. An example secondary fuel nozzle includes a nozzle body delivering fuel, a nozzle housing surrounding the nozzle body and defining air passages for the secondary air to enter and flow toward an end of the nozzle body, and a premix fuel unit positioned upstream of the air passages injecting fuel delivered by the nozzle body into the secondary air for premixing prior to combustion.