PORT ST. LUCIE, Fla. -- Strengthening the pitching staff is a priority this season for the Marlins. A pair of prospective arms met with opposite results against the Mets in Sunday's 10-3 loss at First Data Field.
Right-hander Pablo Lopez, ranked as the organization's No. 24 prospect by MLB Pipeline, worked the final 1 1/3 innings. He struck out three batters and walked another.
"Pablo looked good, he was aggressive," Marlins manager Don Mattingly said. "It was encouraging."
The results weren't as positive for Zac Gallen, the No. 14 prospect. The righty worked a forgettable fifth inning, allowing five runs on six two-out hits, including a homer by Mets backup catcher Jose Lobaton.
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"He got a couple quick outs and then he just got hit around a little bit," Mattingly said. "I don't know until I look at the video if the balls were getting on the plate or not getting the ball where he wants. You can't really tell with him because he's always composed and under control. It'll be interesting to see him the next time out."
In addition, Justin Nicolino came out of the bullpen to throw two scoreless innings. He allowed just one hit and walked one.
"Right now, we're going to stretch him out from the standpoint that we don't know what's going to happen," Mattingly said. "It's either a long man or a starter."
Top two prospects contribute
Outfielders Lewis Brinson and Monte Harrison, the Marlins' top two prospects, respectively, gave Miami a glimpse of what they bring to the table. Both came to the Marlins from Milwaukee in the Christian Yelich trade.
Each went 1-for-2, with Harrison drilling a double down the left-field line, scoring Brian Anderson for a fourth-inning run. Harrison was the Marlins' designated hitter and batted sixth in the order.

Brinson, playing center field and batting second, reached base twice. He was hit by a pitch in the third and followed with a fifth-inning single.
Lee on the basepaths
Braxton Lee is getting looks with his defensive play, but Mattingly would like to see the 24-year-old outfield prospect be a better basestealer.
"He's got a cannon, so he's not going to get overlooked," Mattingly said on Sunday. "He's going to get plenty of looks out there. Our guys love him [defensively]. We feel like he's a premium defender."
Baserunning is what Mattingly said he would like to see Lee improve upon this spring.
"The one thing I think we need to work on is baserunning metrics and decisions he makes out there. The stolen-base percentage is what we need to continue to work on for him to be confident in his steals," Mattingly said.
Infield solid
When asked about his infield on Sunday, Mattingly did not hesitate for an answer.
"I think we'll be solid," Mattingly said. "Our infield will pretty much be back with Martin [Prado] coming back. Justin [Bour] got better defensively for us. He shows that as long as he's on the field, he's going to be productive for us. Starlin [Castro] we know can hit. J.T. [Realmuto] and [Tomas Telis] gives us two guys that we know can really defend."
Up next: The Marlins host a split squad of World Series champion Astros at 1:05 p.m. ET on Monday at Roger Dean Chevrolet Stadium (listen live on Gameday Audio). Right-hander Jose Urena, a candidate to start Opening Day, makes his Grapefruit League debut for Miami. He will be opposed by Houston righty Francis Martes, a former Marlins prospect.