DENVER -- He’s a 23-year-old rookie, and on Friday night, no one would have blamed him if he had some anxiety about what he was about to do: pitch his first game at Coors Field.

But for Sandy Alcantara, it isn’t about venue. It’s about mindset.

“I don’t think it matters where he’s pitching, to be honest with you,” Marlins manager Don Mattingly said after Miami’s 3-0 loss to the Rockies. “When he’s aggressive, his stuff is good enough that it’s gonna play.”

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Alcantara was aggressive Friday night at 5,280 feet above sea level. And indeed, his stuff played. His fastball touched 98 mph, and when he came out of the game, he had thrown seven strong innings, giving up two runs on three hits, walking four and striking out two.

Alcantara became only the seventh road pitcher since 2014 to go at least seven innings at Coors Field while giving up two or fewer runs and three or fewer hits. The other six are the D-backs’ Luke Weaver (May 4, 2019), the Cardinals’ John Gant (August 25, 2018), the Cardinals’ Adam Wainwright (May 27, 2017), the Nationals’ Stephen Strasburg (August 19, 2015), the Cardinals’ Lance Lynn (June 23, 2014) and the Dodgers’ Clayton Kershaw (July 4, 2014).

Alcantara would really only like one pitch back: a slider he left over the heart of the plate to Ryan McMahon, who deposited it over the wall in right-center field for a two-run homer in the second inning.

He escaped a jam in the third, when with one out and two runners on, he got fly outs from Yonder Alonso and Raimel Tapia. Then in the fifth, he was facing Nolan Arenado with runners at first and second with one out, but induced a 6-4-3 double play to end the threat.

Alcantara has had an up-and-down season, mixing in strong starts with subpar ones. Mattingly said the bottom line is this: when he attacks hitters with his 97 mph fastball, he succeeds. When he tries to nibble and is throwing 93, well, that’s not good.

“I’m not quite sure what it is, honestly,” Mattingly said about why Alcantara vacillates between the two poles. “It’s kind of a question mark in our minds why one game it’s one way [and the next, it’s not].”

Alcantara may just be finding consistency, both in mindset and results. He has a 3.20 ERA over his three August starts, following his last July outing in which he gave up a career-high seven runs over 4 2/3 innings against the Twins. His average four-seam fastball velocity has ticked up, from an average of 95.4 mph before August, to 95.9 mph this month.

“When I come out in the first inning and don’t let the hitters get a chance [to do damage], I go deep into the game,” Alcantara said. “Just be aggressive every time, and keep taking advantage of it.”

Alcantara was the top pitching prospect acquired out of Miami’s flurry of trades following the 2017 season, coming to the club as part of the deal that sent Marcell Ozuna to the Cardinals. His development and the realization of his potential are among the keys to the Marlins’ rebuilding process.

So if he looks back on this month and can see it as a turning point in his young career, shedding any timidity on the mound will have been central to attaining consistency.

“He gets in trouble when he’s nicking around the strike zone,” Mattingly said. “When he comes out aggressive and with the mindset that he’s gonna give them his best stuff, he’s pretty much like this.”