The Miami Marlins have built a reputation for finding intriguing young talent, particularly on the international market, and one of their most fascinating pitching prospects may still be years away from reaching the majors.

Right-hander Kevin DeFrank just turned 18 years old last month (August 11), but there's already plenty about the Dominican prospect that makes him stand out. He's currently regarded as Miami's No. 5 prospect and possesses the kind of physical tools that immediately grab attention. At 6-foot-5, he already has the frame of a much older pitcher, along with an athletic build and impressive arm speed.

Then there's his fiery fastball. According to MLB.com's scouting report, DeFrank's four-seam fastball operates around 97 mph and can reach triple digits. That kind of velocity would be impressive from a fully developed professional pitcher. From a teenager who has not yet reached his 18th birthday, it becomes considerably more intriguing.

Defrank's power stuff at this age is impressive enough, and the fact that he's consistently throwing it for strikes separates him from most DSL pitchers," his official prospect analysis states, while pointing out his age and inexperience. "His command still has a ways to go, as expected from someone his age, but he has the athleticism and repeats his delivery well enough to already show average control. Teenage pitching prospects are incredibly risky, but he's checking every box you'd want to see, including impressive makeup and leadership."

The fastball isn't his only weapon, either. DeFrank features a changeup with significant sinking action and a developing slider as part of his repertoire. MLB's scouting grades give his fastball a 70, his changeup a 60, and his slider a 55, while his control is currently graded at 50.

Naturally, there is plenty of development still ahead.

Teenage pitchers are among the biggest gambles in professional baseball. Their bodies are still developing, their workloads must be managed carefully, and their command often takes much longer to mature than their raw stuff. DeFrank is no exception.

DeFrank's first professional season produced some encouraging results: he went 0-1 with a 3.19 ERA and 34 strikeouts over 31 innings. An injury slowed his development in 2026, making patience even more important as Miami decides how aggressively to advance him.

The young hurler needs time to add strength, refine his command, and learn how to consistently turn his impressive arsenal into results against increasingly advanced hitters. Miami and president of baseball operations Peter Bendix can afford to take the long view with a pitcher this young.

That may ultimately be the most exciting part of his story.

If everything develops according to plan, DeFrank could be approaching Double-A by his age-19 season and potentially knocking on the door of the major leagues before his 21st birthday.

For now, however, Marlins fans should simply monitor the development of a teenager who already owns some remarkably grown-up pitching tools. DeFrank's ceiling is enormous. The timetable is uncertain, but the ingredients for something special are clearly there.