Diamondbacks Yoan Lopez Dominating Double-A


Diamondbacks pitching prospect Yoan Lopez has gotten off to a hot start this season after struggling during his Cactus League Spring Training debut in March.  After allowing 12 runs in 13 and 2/3 innings this spring, Arizona assigned him to minor league camp hoping for better results. 

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Those results have come quickly for the young right-hander as he’s shown rapid improvement since seeing his first professional action.

When Lopez was first signed in the offseason for what was at the time the highest signing bonus in the history of international amateur players, there was talk of him immediately competing for a rotation spot.  That talk died down quickly, but he’s shown flashes of why Arizona invested that much money in him.

Last season in the Cactus League, Lopez registered a 3.12 ERA and 28 strikeouts across seven starts in the Serie Nacional League.  Scouts were enamored by his velocity and swing and miss ability on the mound.

Since then, his fastball has dropped from the mid to high 90s to low 90s, but his control has progressively gotten better over each one of his minor league starts.  Diamondbacks’ manager Chip Hale noticed the dip in velocity too, but cautioned that velocity isn’t everything:

“I think the fastball hasn’t been quite the velocity that we thought, but 92 is nothing to sneeze at, especially when you can make it move and control it, spot it,” said Hale according to The Arizona Republic.

Control is something that Lopez struggled with during the spring and Arizona coaches have preached consistency during his development. “He’s got to get a better idea of his delivery and be more consistent with it so he can start out of the chute strong and finish strong,” Arizona Pitching Coach Mike Harkey said to The Arizona Republic. “That’s always the learning curve. It takes a little bit of time, especially for younger, international players who haven’t really faced a lot of competition over there.”

He’s certainly finished strong for the Mobile Baybears going 5+ innings in each of his four games pitched and posted a 2.70 ERA. During that time period, he’s struck out 18 while stranding 84.7 percent of base-runners on base.  His 18 strikeouts are second most on the team behind fellow top prospect Aaron Blair and his 1.24 WHIP is third amongst Mobile starters. 

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More importantly, he’s looked poised on the mound while attacking the strike-zone and mixing in his changeup, curveball, and slider.  That slider has been his bread and butter with excellent movement and bite and currently looks like a plus secondary pitch that could quickly earn him a promotion to Triple-A.

Lopez’s best start came on April 23rd against the Montgomery Biscuits when he allowed one earned run on five hits across seven innings.  He struck out eight and more notably didn’t issue a walk.

With improving control and the confidence to attack the strike-zone, Lopez is on the road to being promoted to Triple-A before the All-Star break.  Arizona will be patient with his development, but if he can maintain his success he could see the Majors as a September call-up.