Less than 24 hours after opening the final leg of a three-city trip with an extra-innings walk-off loss, the Marlins (11-15) were handed one of their most lopsided defeats, 7-2, by the Nationals on Saturday afternoon at Nationals Park. Miami fell to four games below .500 for the first time since April 10, when the club was 2-6.

• Pair of top prospects headed to Double-A

Right-hander Paul Campbell was chased during a five-run fourth inning in his first Major League start, while veteran southpaw Patrick Corbin held the Marlins in check over seven frames. Miami is limping to the finish line of a 10-game trip, in which it has lost six of nine.

What's going wrong
• Campbell, a Rule 5 Draft pick, allowed five runs (four earned) on nine hits with four strikeouts in 3 2/3 frames. Only Yan Gomes’ two-run homer went for extra bases, With Elieser Hernandez and top prospect Sixto Sánchez sidelined, Campbell was the most recent rookie to get a shot at the rotation, joining the likes of Nick Neidert and Daniel Castano.

"Just to keep my composure, keep my head in the game at all times, learn to slow down just a smidge," Campbell said of the lesson learned. "I think it's extremely important to be on every pitch, especially at this level. I have my catcher come up to me, [Miguel Rojas] come up to me, and we went over a few different things. Those guys are awesome and they're good leaders, and I appreciate all my teammates having my back."

• Jesús Aguilar homered for the sixth time in eight games, but the lineup was relatively quiet otherwise. Aguilar has had to do the heavy lifting with Starling Marte, Brian Anderson, Jazz Chisholm Jr. and Jorge Alfaro on the injured list. Miami is averaging 4.1 runs per game this season, but the club has scored three or fewer runs in half its contests.

Middle-of-the-order bats Garrett Cooper and Adam Duvall went hitless in seven plate appearances with four strikeouts on Saturday. On the trip, they have combined to go 7-for-61. Cooper has homered and doubled. Duvall doesn't have an extra-base hit or an RBI during this stretch, with 14 strikeouts and one walk.

Manager Don Mattingly noted Duvall’s timing has been off, which is keeping him out of position where he can’t control the barrel. As for Cooper, Mattingly sees him trying to pull the ball rather than using the whole field like he has in the past.

“In general, obviously the offense is still kind of not really catching a groove, and we don't seem to be able to sustain anything,” Mattingly said. “We have a couple of days where we swing the bats good, and then it seems like we get off track. Again, I think we're capable, we've just got to get more consistent."

What's going right
Rookie right-hander Jordan Holloway pitched a scoreless sixth and seventh, giving him seven shutout innings across four outings this season. Miami's No. 22 prospect has allowed just two hits, with one walk and seven strikeouts. His WHIP is 0.43 and his opponents' batting average is .087.

The 24-year-old continued a pair of positive trends in his latest appearance: He threw 19 of his 29 pitches for strikes, and his arsenal relied on a slider (48.3 percent), four-seamer (41.4 percent) and curveball (10.3 percent) mix. In 2019 at the Class A Advanced level, Holloway walked a Florida State League-high 66 batters. Holloway credits advice he received from then-pitching coach Reid Cornelius.

"Honestly, just staying in the zone and getting ahead of hitters," Holloway said. "That really has put me kind of more in the driver's seat. Obviously, the slider has been really good, fastball command has been a lot better, and all my pitches being able to mix that stuff and get ahead of hitters has really helped."

While the organization views Holloway as a starter, his performance and arsenal might steer him to a relief role in the future. Holloway would like to start, but he would like the opportunity to help the big league club in any way possible more.

“He’s gaining confidence,” Mattingly said. “You can see it as he goes and pitches pretty much clean innings. ... I think you see a guy that looks like he's crossing some barriers, throwing strikes, he's getting his offspeed over, he's mixing. We've seen a guy with really, really good stuff, and he has started to put it together. … Got a little taste last year, but obviously a guy that's on the hunt, got big stuff. Now he's throwing strikes, he's throwing strikes with his offspeed, so he's a guy that's on the move. He's throwing the ball really good.”