Rainey allowed four runs on four hits and a walk over two-thirds of an inning during Tuesday's spring loss to the Cardinals.
Rainey was acquired from the Reds for Tanner Roark in December and his first unofficial outing in a Nationals uniform was forgettable. The hard-throwing right-hander has historically struggled with walks (6.2 BB/9 at Triple-A Louisville in 2018), but that was of no concern Tuesday as he fooled no one and threw 12 total pitches to the seven batters he faced.