Thompson gave up one hit and struck out three over two scoreless innings of relief in an Opening Day loss to Atlanta.
The 25-year-old righty entered the game in the sixth inning with the Nationals down 4-2 and fanned Austin Riley and Michael Harris to keep things close for the home squad. Thompson's role is fairly undefined to begin the season -- starter Patrick Corbin couldn't complete four innings Thursday, taxing the Washington bullpen right out of the gate -- but if he keeps getting the job done, he could work his way into a high-leverage role.