MIAMI -- When the Marlins acquired right-hander Sandy Alcantara as part of the Marcell Ozuna trade in 2017, his elite velocity stood out. MLB Pipeline's scouting report stated both his breaking ball and changeup needed work, and his command was suspect. All of those factors combined could have prevented him from being a starter in the Majors.

Less than four years later, Alcantara's evolution into one of the game's top under-the-radar pitchers continues. Despite being the tough-luck loser in Tuesday night's 4-2 loss to the Cardinals at loanDepot park, he matched a career-high 10 strikeouts across six innings. Things quickly unraveled in the sixth, as the frame opened with two infield hits and a walk. A passed ball scored the first run, and then another raced home on a groundout when first baseman Garrett Cooper double clutched on a throw home. Yadier Molina followed with the go-ahead sacrifice fly to center.

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"We faced a good pitcher tonight," Cardinals manager Mike Shildt said during a Zoom call. "Alcantara, man, he's got nice stuff. We had him over here, and this guy has really developed a skill set. He's repeating his delivery, changeup's good, sinker's good, command's way better, he can control what he's doing."

Alcantara, an All-Star in 2019 but very much a work in progress, has started some of Miami's biggest games of the past year -- Game 1 of both the ‘20 National League Wild Card Series and NL Division Series, the playoff clincher at Yankee Stadium and two consecutive Opening Days. With right-hander Elieser Hernandez landing on the injured list, top prospect Sixto Sánchez experiencing a setback and left-hander Trevor Rogers failing to pitch deep into Monday’s game, the Marlins need their ace to step up with some uncertainty surrounding the rotation.

The 25-year-old righty has kicked it into another gear since Sept. 15. In Alcantara's last five regular-season starts, he is 1-2 with a 1.72 ERA, with 22 hits allowed and 35 strikeouts in 31 1/3 innings.

Alcantara's biggest growth has been in the swing-and-miss department. There was concern early on in his Marlins career that his strikeout totals wouldn't add up to his quality stuff and velocity. Alcantara recorded just 7.9, 6.9 and 8.4 strikeouts per nine innings through his first three seasons with the Marlins, respectively. In 2020, that number improved to 10.5. In two ‘21 starts, he has fanned batters at a 35.4 percent clip. At one point on Tuesday, a dominant Alcantara fanned six straight batters. According to the Elias Sports Bureau, it marked the seventh time in club history a Marlin had struck out six or more in a row. Alcantara also became just the third Marlins pitcher to fan 10 or more Cardinals batters, joining José Fernández and A.J. Burnett.

"I'm just trying to learn something every time," Alcantara said during a Zoom call. "Nobody's perfect in this life. I think I've been one of those guys [where I've] tried to learn something every day. I've been improving a lot. I've been improving myself, my routine, my release point all the time. I think that made me feel real comfortable, and that has helped me to get a lot of strikeouts."

Marlins manager Don Mattingly credits that progress to pitching coach Mel Stottlemyre Jr. not giving up on Alcantara's changeup, which the righty repeatedly called his best pitch during Spring Training. That has become his third-most-used offering in 2021, with six of his 17 strikeouts coming on it.

According to Statcast, all five of Alcantara's pitches -- the sinker, four-seamer, changeup, slider and curveball -- showed increased velocity on Tuesday. He even reached a maximum velo of 99.3 mph, his fastest since March 31, 2019. He’s also found more trust in his four-seamer, which he threw 23 times, second most of his 93 pitches. Alcantara has become a complete pitcher.

"He's got the weapons,” Mattingly said during a Zoom call. “Using more elevation now, so he's throwing the ball up in the zone. Now with the changeup, you start to scrape that up and down. It's a lot to cover. He's throwing strikes, and that's not even talking about the slider yet. ... Just got weapons, and he's learning to use them and where, and that's important. That's how you get tickets by knowing where you want to go and when. So he's just developing, he's going to keep getting better."