Example dual-burner assemblies for cookboxes of gas grills are disclosed. An example dual-burner assembly includes a first burner tube and a second burner tube. The first burner tube has a first maximum heat output. The second burner tube has a second maximum heat output. The second burner tube is spaced apart from the first burner tube by a distance of no more than 0.750 inches. The second maximum heat output is less than the first maximum heat output.