Preheat oven to 400 degrees.
Stir together garlic, sage, salt, pepper, and olive oil in a small bowl. Rub mixture all over pork.
Heat a large, heavy saute pan over medium-high heat. Add vegetable oil. Add pork, and brown all over, about 4 minutes.
Transfer pan to oven. Roast pork, turning occasionally, until an instant-read thermometer inserted into thickest part registers 145 degrees to 150 degrees, about 20 minutes.
Transfer pork to a cutting board; tent with foil, and let rest 10 minutes before slicing.
