WASHINGTON -- Josh Harrison has been a member of the Nationals for only four days, and his enthusiasm already has made an impression.

“He loves to have fun,” manager Dave Martinez said. “He was one of the guys yesterday that was cheering awfully loud for the boys. I love having him around. He’s been good so far. He’s a veteran guy, he can help us in many different ways.”

The Nationals hope Harrison can help with his bat on Thursday. He is in the lineup to make his debut in the designated-hitter role. Harrison will hit sixth as Howie Kendrick remains hampered by upper back stiffness.

A healthy Harrison is eager to get back on the field after he had been sidelined by injuries. Last season, he was limited to 36 games with the Tigers. He has slashed .273/.313/.401 over his nine-year career. Martinez noted Harrison has been hitting well during batting practice since signing with the team on Monday after being released by the Phillies on July 21.

“He’s a student of the game,” Martinez said. “I’ve been talking to him a little bit during the games and listening to him. He pays attention. He understands the game, so that’s kind of nice.”

Strasburg progressing

Stephen Strasburg is no longer experiencing the discomfort in his right hand that caused him to miss his first two starts of the season.

“He’s in a good spot right now,” Martinez said. “He’s not feeling that little nerve issue anymore. He feels fine.”

Strasburg is to throw off flat ground on Thursday, the same day Erick Fedde is making his second start in Strasburg's spot. Strasburg threw only fastballs on Wednesday, but he is aiming to expand his pitching program.

“Today he’s going to mix in a couple breaking balls, fastballs on flat ground,” Martinez said. “If that goes well, next time throwing will be off the mound. But he’s doing a lot better.”

The Nationals have yet to determine if Strasburg will need to face live hitters before he is cleared to return. If so, there is a possibility he could pitch in the sim games the Nats are planning to hold this weekend in place of their postponed road games against the Marlins.

Bullpen booster

In the back end of a bullpen that includes veterans Sean Dootlittle, Will Harris and Daniel Hudson, Tanner Rainey is standing out in his third Major League season.

The 27-year-old right-hander has thrown 3 2/3 hitless frames with six strikeouts over four appearances.

This season, he has relied on his four-seamer for 70.8% of his pitches, and his slider for the rest.

“Since we got him last year, he’s matured a lot,” Martinez said. “The biggest thing with Rainey -- he’s got unbelievable stuff -- was his ability to throw strikes when he needed to. He’s done that. He proved that he could do that. He’s worked on throwing another pitch, which he hasn’t thrown yet but I’d like to see him use it more because it’s pretty effective, which is a changeup. … I think he deserves a chance to pitch in the back end of the bullpen, so we’re going to use him like that.”

Rainey was 2-3 with a 3.91 ERA over 48 1/3 frames in 52 games for the Nationals in 2019.