When Sandy Alcantara said he was “100 percent” ready to go earlier in the week, the 24-year-old sure wasn’t kidding.

Antsy for weeks to get the season going, Alcantara rose to the challenge of being an Opening Day starter, striking out seven in 6 2/3 innings on Friday night in the Marlins’ 5-2 win over the Phillies at Citizens Bank Park.

“His stuff is overpowering, right, when he stays aggressive and attacks the strike zone,” Marlins manager Don Mattingly said. “Then we were able to get him some runs, which takes the pressure off and gives us some breathing room.”

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The Marlins won on Opening Day for the first time since 2014.

Brandon Kintzler collected the save, the 50th of his career. And Mattingly won his 277th game as manager of the Marlins, moving him into second place on the all-time list, ahead of Fredi Gonzalez (276). Jack McKeon is the franchise leader with 281.

An All-Star in 2019, Alcantara continues to show signs that he’s ready to take the next step. Coming out throwing heat, the lanky right-hander sent a signal early that he was ready to be on the attack. In a clean first inning, he struck out Rhys Hoskins and Bryce Harper, who went down swinging on a 98.1 mph four-seam fastball.

“That gave me 100 percent confidence,” Alcantara said. “I was happy to be outside, and no matter what happened, just give 100 percent.”

Alcantara allowed two runs, one earned, on three hits with two walks. The Marlins’ starters have been built up to throw close to 100 pitches, and Alcantara’s night ended after 87 pitches, with 14 swinging strikes. His four-seam fastball, per Statcast, maxed at 98.8 mph, and he mixed in a 98.2 mph sinker. Alcantara induced seven ground-ball outs.

"His stuff was really good tonight," Phillies manager Joe Girardi said. "That power sinker that he has, the changeup and the breaking ball. I thought our at-bats were better the second time through the lineup, but he was pretty dominant tonight."

Alcantara got some support from the three veteran newcomers -- Jonathan Villar, Jesús Aguilar and Corey Dickerson.

Miami claimed the early lead in the third inning on Villar’s sacrifice fly. And after Didi Gregorius’ homer off Alcantara in the fifth inning, Aguilar belted a two-run homer off Aaron Nola. Dickerson doubled and scored on a wild pitch, and Garrett Cooper added an RBI double in the four-run frame.

“I think we're going to be all right,” Aguilar said. “We're going to hit, for sure. Now we have to keep going. We have 59 games to play. It's going to be a short season, but we're going to enjoy it.”

Upgrading the offense was Miami’s top offseason priority. As important as that will be to overall success, the pitching ultimately will define the season.

In year three of their building process with Derek Jeter as chief executive officer, the Marlins like their chances in a “60-game sprint” based on the quality of their starting pitching. As a club, they have bought into the notion that they have as good a chance as anyone to compete. Alcantara did his part pointing the club in the right direction.

“This is what we've been building and moving towards,” Mattingly said. “This is the club that Derek and those guys talk about. We want a club that's athletic, and exciting, and aggressive. We're moving in that direction. We're getting more speed. We know we've got pitching, and we've got pitching coming. I think we're seeing the offense, with the additions of the guys this year, those are three quality guys in your lineup.”

With his power sinker and changeup, Alcantara is known for getting his share of ground balls. He picked up a huge one in the sixth inning, getting Andrew McCutchen to tap into a 6-4-3 double play.

“I don't get scared when I have men on base,” Alcantara said. “I believe in what I've got. I just tried to throw a strike and get a ground ball. This means a lot. We're trying to be like a family here, and help each other.”