Justin Martinez is a 25-year-old right-handed pitcher from the Dominican Republic making his mark with the Arizona Diamondbacks. Born in Bonao on July 30, 2001, he made his MLB debut on July 7, 2023, and his 2024 season — a 2.48 ERA with 91 strikeouts in 72.2 innings — made it clear he belongs at this level.
Quick Facts
- Full name: Justin Martinez
- Position: Pitcher
- Team: Arizona Diamondbacks
- Jersey number: 17
- Bats / Throws: Right / Right
- Height / Weight: 6’3″ / 225 lbs
- Date of birth: July 30, 2001 (25 years old)
- Birthplace: Bonao, Dominican Republic 🇩🇴
- MLB debut: July 7, 2023
Background
Martinez grew up in Bonao, a city in the Dominican Republic with deep baseball roots. The Diamondbacks spotted his potential early and brought him through their minor league system, developing his arm before giving him his big-league shot at just 21 years old.
Professional Career
His 2023 debut was a learning experience — 10.0 innings, a 12.60 ERA, and the kind of growing pains that come with facing MLB hitters for the first time. But Martinez didn’t let it shake him.
2024 was a different story. He posted a 2.48 ERA across 72.2 innings, struck out 91 batters, went 5-6, and held a 1.31 WHIP — numbers that showed real, competitive stuff and solid command for a pitcher still in his early twenties.
In 2025, Martinez is back with Arizona and working to lock down a consistent role. Through 15.1 innings he carries a 4.11 ERA, a 1.24 WHIP, a 1-2 record, and 22 strikeouts — still building, still pushing.
Career Stats
- 2025 — Arizona Diamondbacks: 4.11 ERA | 1-2 | 22 K | 1.24 WHIP | 15.1 IP
- 2024 — Arizona Diamondbacks: 2.48 ERA | 5-6 | 91 K | 1.31 WHIP | 72.2 IP
- 2023 — Arizona Diamondbacks: 12.60 ERA | 0-0 | 14 K | 2.40 WHIP | 10.0 IP
Awards and Records
Martinez hasn’t collected individual hardware yet — no MVP, Silver Slugger, or Gold Glove. His career is still being written, with the focus squarely on establishing himself as a reliable arm in the Diamondbacks’ staff and continuing to sharpen his effectiveness.
One Thing Worth Knowing
Martinez reached the majors at 21, part of a wave of Dominican talent arriving in MLB younger and younger. His story is still in its early chapters — and after what he showed in 2024, those chapters are worth following closely.
