"He threw some good sliders and he also threw some good changeups, but also some good sinkers," McCatty said.
Grace, who was put on the 40-man roster in November, went a combined 5-1 with three saves and a 1.17 ERA in 50 games between Double-A Harrisburg and Triple-A Syracuse in 2014. He was promoted to Syracuse on June 16 and posted a 1.30 ERA and a .194 opponents' batting average in 28 appearances at the highest level of the Minor Leagues.
Grace, 26, features a heavy, sinking fastball, and he induced ground balls at a rate of 69 percent in 2014. He was selected by the Nationals in the eighth round of the 2010 First-Year Player Draft out of UCLA.
"We are going to get him in as many games and see what happens," McCatty said. "Obviously, he is on the roster. You can never find too many left-handers to use. This is really his first experience in a big league camp. Knowing he is throwing the ball well, we are going to have him face guys. That's what you have to do. It's all part of it. You get the experience and get over the initial excitement, shock, whatever you want to call it when you get out there as a young kid. He has real good stuff."
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the Time. He also can be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.