WASHINGTON -- Looking to boost their taxed bullpen, the Nationals recalled right-hander Steven Fuentes -- their No. 22 prospect, per MLB Pipeline -- on Tuesday. They optioned righty Ryne Harper to the alternate training site in a corresponding move.

Fuentes, 23, has been in Washington¡¯s organization since 2014. He reached Double-A in ¡®19 (5-4, 2.69 ERA, 63 2/3 innings), and he spent last season at the alternate training site. This year, he has been stretched out to 85-90 pitches at Fredericksburg, Va. His first appearance with the Nationals will be his Major League debut.

¡°He threw well his last outing,¡± manager Dave Martinez said. ¡°He gives us a little bit more length, a fresh arm.¡±

Martinez lauded Fuentes for consistently throwing in the strike zone. He highlighted Fuentes¡¯ two-seam fastball, four-seam fastball and what he described as a ¡°really good changeup.¡±

¡°I just want him to go out there when he gets an opportunity to pitch, just go out there, relax and utilize all his pitches,¡± Martinez said. ¡°I told him, ¡®Don¡¯t change a thing because you¡¯re here. Just throw strikes, let your defense play and just get outs for us.¡¯¡±

The Nationals have had to keep a close eye on the bullpen¡¯s workload amid the starting rotation¡¯s recent struggles. Harper threw a combined three innings out of the ¡®pen in back-to-back games, Sunday and Monday.

¡°He understands this is part of the game,¡± Martinez said. ¡°It really stinks. But when you¡¯re using your bullpen the way you¡¯re using it right now, we¡¯ve got to get some fresh arms in here and we¡¯ve got to keep guys healthy. ¡­ I¡¯m sure that you¡¯ll see Ryne Harper again, but we¡¯ve got to bring somebody in that can give us some length.¡±

Matchup decisions
Given Ryan Zimmerman¡¯s decade-plus success against Adam Wainwright, it was notable that the veteran was not in the lineup against the Cardinals starter on Tuesday. Zimmerman is 13-for-37 (.351) in the matchup, including a home run last week.

Martinez, though, wants fellow first baseman Josh Bell to get into a rhythm and carry the momentum of his double on Tuesday. Bell is 7-for-23 (.304) with a homer and five RBIs in his career against Wainwright.

¡°[It was] very tempting [to start Zimmerman], but the good news is that we could plop him in if something¡¯s happening anywhere. He¡¯s had unbelievable success against Wainwright,¡± Martinez said. ¡°But I looked at the numbers -- Bell¡¯s hit him well, too. We really need to get Bell going, and he needs to get his at-bats. I was impressed with the way he hit the ball yesterday to left field, so that¡¯s a good sign. We¡¯ve got to get him going. Once we get him going, we¡¯ll start scoring a lot more runs.¡±

Prospect Romero sidelined
The Nats¡¯ No. 18 prospect, left-hander Seth Romero, suffered another setback. Romero, 25, injured his ribs while throwing last week at the alternate training site, Martinez said. His status is day to day.

¡°He¡¯s not throwing the ball right now,¡± Martinez said. ¡°He¡¯s going to be out for a while. As soon as we can get him healthy, he¡¯ll be back on the mound.¡±

Romero, the Nationals¡¯ first-round MLB Draft pick in 2017, made his Major League debut last August. He was shut down weeks later after breaking his right hand and requiring season-ending surgery.