Preheat the grill to medium-high heat.
Pat the chicken breasts dry with paper towels.
In a small bowl, mix together the olive oil, garlic powder, smoked paprika, salt, black pepper, and dried oregano.
Brush the spice mixture evenly over both sides of each chicken breast.
Place the chicken breasts on the grill and cook for 6-7 minutes on one side without moving.
Flip the chicken breasts and grill for another 6-7 minutes, or until the internal temperature reaches 165°F (75°C).
Remove the chicken from the grill and let it rest for 5 minutes before slicing and serving.