Entering Tuesday's slate of games, the Washington Nationals ranked No. 23 in team ERA at 4.58.That is a massive improvement compared to where they were at the beginning of the season, and credit has to be given to the coaches and everyone on the pitching staff for bouncing back to get to this point. However, with that said, there are still clear weaknesses when it comes to that overall unit, and that's why the organization continues to search for answers.Someone the Nationals turned to was right-hander Riley Cornelio. There was plenty of buzz surrounding the 26-year-old coming into the season, and it seemed like he could become a key contributor at some point. But when he made his MLB debut on April 24, he had a disastrous outing that caused Washington send him back to Triple-A Rochester.About a month-and-a-half later, though, Cornelio is back up with the big league squad. And this time, both parties are hoping he can stick in the bullpen for the long haul.Nationals Hope Riley Cornelio Plays His Way Into Extended MLB StayWashington Nationals pitcher Riley Cornelio | Arianna Grainey-Imagn ImagesIt was a bit of a surprise when the Nationals announced they had optioned right-handed reliever Cole Henry and Cornelio was his replacement. After all, Cornelio was tagged for two earned runs across three innings of work with four walks and one strikeout in his debut, as he looked overmatched against the Chicago White Sox. And when he didn't light the world on fire upon his return to Rochester, it seemed like it might be a while before he was recalled to The Show.But Washington felt like it was time to give him another look. And while his second career MLB outing on June 7 had some bumps along the way -- one earned run allowed across two innings with three walks and one strikeout -- he looked much more composed. And that result not only gave Cornelio another opportunity to prove he belongs on the major league mound, but it also gave Washington a chance to envision having him be part of their bullpen for the long run."Part of the thought process of last time was, we told him he was coming out for one outing, basically just to give him a chance to dip his toe in the water before he comes up here – hopefully longer-term," manager Blake Butera said, per Jessica Camerato of MLB.com. "... So hopefully this time, there's some more confidence and things are a little bit slower for him."Nationals Gave Clear Instructions for Him to Have SuccessWashington Nationals pitcher Riley Cornelio | Reinhold Matay-Imagn ImagesCornelio admitted he felt a bit more ready to pitch in the bigs this time around, and that helped him get out of some jams against the Arizona Diamondbacks to limit the damage he allowed. But for him to be successful, he has to reduce his walk rate. And the Nationals have told Cornelio exactly what he needs to do to make that happen."The focus for Riley is, he has really good stuff. We want him to attack the zone. He's got to throw strikes. These hitters – whether you're walking guys or even just behind in the count – they're going to capitalize, no matter how good [his] stuff is," Butera added.The 26-year-old isn't the first, nor will he be the last, pitcher to be told that he has to attack the strike zone more often in the majors. That's something ace Cade Cavalli had to figure out early on this season, and since he's made those adjustments, he's been performing like a high-end starter. Washington seems to be confident that Cornelio can do the same. So if he's going to remain in the bigs and be a long-term member of this pitching staff, then he'll need to make those improvements quickly to show the Nationals he belongs at this level.Add us as a preferred source on GoogleFollow