Diamondbacks' Rodriguez Showcases Improved Curveball in Spring Training

Pitcher credits offseason conditioning and pitch development for late-season surge in 2025

Feb. 27, 2026 at 8:22am

Got story updates? Submit your updates here. ›

Arizona Diamondbacks left-handed pitcher Eduardo Rodriguez is generating optimism during spring training after ending last season on a stronger note, crediting his improved fitness and a refined curveball for his late surge. Rodriguez delivered two scoreless innings in his spring debut, with his fastball velocity ticking up to an average of 93.1 mph, surpassing last year's 92 mph.

Why it matters

Rodriguez's performance this spring is crucial as the Diamondbacks aim to stretch out their starting rotation while waiting for ace Corbin Burnes to return midyear. Additionally, uncertainty surrounds Merrill Kelly's readiness due to a back injury, heightening the need for Rodriguez to provide reliable innings in the early schedule's difficult stretch.

The details

Rodriguez revealed that he lowered his weight from 255 pounds at the start of last season to 232 this offseason, working extensively on his mechanics and conditioning. Midway through last season, Rodriguez began introducing a true curveball into his repertoire, increasing its frequency as the campaign progressed. This new pitch quickly showed its value with better opponent contact results compared to his slider.

  • On Thursday, Rodriguez delivered two scoreless innings in his spring debut.
  • Last season, Rodriguez struggled in the first half with a 5.94 ERA before the All-Star break, but improved to a 4.01 ERA in the latter half and posted a 3.38 ERA in September.

The players

Eduardo Rodriguez

A left-handed pitcher for the Arizona Diamondbacks who is aiming to build on a strong finish to the 2025 season.

Torey Lovullo

The manager of the Arizona Diamondbacks, who has noticed Rodriguez's improved conditioning and pitch development this spring.

Corbin Burnes

The ace pitcher for the Arizona Diamondbacks who is expected to return midway through the 2026 season.

Merrill Kelly

A starting pitcher for the Arizona Diamondbacks who is dealing with a back injury, creating more pressure for Rodriguez to provide reliable innings early in the season.

Jose Fernandez

A 22-year-old shortstop on the Diamondbacks' 40-man roster who has impressed in spring training with his power hitting.

Got photos? Submit your photos here. ›

What they’re saying

“I was so excited when I saw the first five outs were on ground balls. I saw a 95 mph so I was really excited by that.”

— Eduardo Rodriguez

“I've been working this offseason on my body, lost some weight, been working in the bullpen on my mechanics and everything, and so far, so good.”

— Eduardo Rodriguez

“I was getting weak contact and swing-and-miss. After that we've been talking about it. … When it looked like a slider, I didn't get swings, they were just taking it. On the ones that looked like a curveball and I had good numbers on vertical and horizontal, those are the ones that got weak contact and swing-and-miss against lefties.”

— Eduardo Rodriguez

“He's come into this camp really ready to go. It's very noticeable. Trying to land certain pitches in certain places, he's very specific about his work. … He's trying to land a different shape breaking ball right now and it looks really good.”

— Torey Lovullo, Manager, Arizona Diamondbacks

“We know there's still more growing he needs to do but driving baseballs the way he is … we know he's been coming on quick and we're paying a lot of attention to him.”

— Torey Lovullo, Manager, Arizona Diamondbacks

What’s next

Rodriguez plans to make his next mound appearance in an exhibition game representing Team Venezuela as he gears up for the World Baseball Classic, which commences on March 5.

The takeaway

Rodriguez's improved conditioning and development of a more effective curveball pitch have generated optimism for the Diamondbacks, who are counting on him to provide reliable innings early in the season as they wait for their ace to return from injury.