Prior to the 2016 season, Giolito was ranked as the top prospect in the Nationals organization and the number-three prospect overall here at Baseball Prospectus, topping a cadre of arms to finish as the highest-ranked pitcher on our big board. He slipped to the middle of the first round (no. 16 overall) of the 2012 draft due to concerns about his elbow, but the Washington Nationals took a gamble and soon Giolito was going under the knife for Tommy John surgery.

The injury to Stephen Strasburg opened a window to see Giolito make his MLB debut. Circumstances allowed for a short stay of execution even once Stras was back into the fold, so Giolito was afforded a pair of starts prior to the All-Star break followed by a spot-start last weekend that we can evaluate.

Game Stats







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When a young prospect struggles in his debut, then it’s easy to chalk it up to nerves of making his first start at the highest level, but Giolito’s four innings of no-hit baseball (which was shortened due to rain) got the masses excited about his potential despite his lone strikeout in the outing. After three starts, however, it’s clear that the right-hander still has a few items left on his developmental agenda before he is ready to shine in the show.

He has made three starts in the past month at the highest level, but Giolito has yet to record an out in the fifth inning and has dealt nearly twice as many walks as strikeouts in his brief exposure. He threw twice as many pitches in his second career start yet chewed fewer innings than in his first turn, following what had been an extremely efficient outing (3.2 pitches-per-batter) with one that was much less so (4.1 pitches per batter in his second start, 3.9 BB/9 in his third). Everything was up in that second turn – runs, hits, walks and strikeouts, not to mention two homers and two doubles given up in a single frame, creating a much different impression despite his facing the same Mets offense in both starts.Getting hit by the Padres without recording a single strikeout against a K-prone offense was the most troubling of all, particularly given that he started the game clean before unraveling in the fourth inning.

Giolito’s stuff has garnered much of the attention over the years as his hype balloon has been inflated, earning 80 grades by multiple sources for both his fastball and his curve, a rare combination for a prospect no matter the pedigree. However, his velocity has not been as advertised, wth an average of 94.5 mph through his first three games according to Brooks, maxing out at 96.7 mph – even with stellar movement (which he did not have), that is merely a plus fastball that would come nowhere close to 80-grade according to any evaluator. Throw in subpar pitch command and the pitch can quickly become a liability rather than an asset, and yet Giolito has thrown heaters on an astounding 75-percent of his pitches this season, essentially playing right into the hands of hitters who can handle mid-90s heat.

His report in the Nats’ prospect top 10 list mentioned that Giolito can sit in the mid-90s (which we have seen) and spike upper-90s velo without much effort (which we have not seen), and the combination of his sketchy pitch command and light movement on the fastball makes the high usage pattern particularly odd. There’s no doubting his curve, however, a pitch that has incredible depth and sharp movement that makes the best hitters in the world turn into pudding. The curve is a legit 80-grade pitch, but the difference between a right-hander with two 80-grade pitches and one who has a dynamite breaker but merely plus fastball is night and day. Throw in the common reality that young pitchers lose velocity as they age, and the possibility exists that Giolito’s curve will be the only offering that sets him apart on the mound.

Mechanics Report Card













I have long been skeptical of Giolito’s delivery due to the lack of power coming from his lower half, as when drafted he had one of the slowest deliveries (from the windup) that I have ever seen, utilizing a pace that I once described as “glacial.” His hip-shoulder separation was borderline elite and he had a long delay to his trigger after foot strike, allowing the hips (and thus his lower half) to do some work after foot strike, but the slow stride wasn’t doing Giolito any favors in terms of extending his release point, generating kinetic energy from the lower half or finding a repeatable timing pattern. It also created the need for a very different timing pattern when throwing from the stretch, as the slow speed of his windup was untenable with baserunners threatening to steal.

He picked up the pace a bit on his journey up the minor-league ladder, so naturally his momentum was one of the first things that I looked at when evaluating his first few starts at the major-league level. I don’t know if this was the element that the Nats sought to address with the right-hander earlier in the season, but if so it would make sense that he struggled at first with the change, as it would naturally disrupt his timing pattern and take some time to master – though it’s worth pointing out that such a timing-related adjustment would likely be necessary and it’s better to tackle the problem in development rather than at the highest level.

Giolito’s balance is very strong during the slow, early phases of his delivery, at least from the windup, but he loses some stability as soon as he adds a slight burst near the end of his stride. He adds some drop and some rock-roll to dent his balance in the Y- and Z- planes, and then the X-plane becomes compromised after foot strike as the spine-tilt kicks in to the glove side from foot strike through release point. His overall balance receives a grade that is above average, but it unravels as soon as he injects some power with the lower half and it remains to be seen whether he can sustain balance over the long haul of a season or even a full-length outing.

Giolito has a ton of power fueling his mid-90s heat, but all of that power comes from immense torque and brute arm strength. He utilizes a combination of upper-body twist and delayed trunk rotation to create incredible hip-shoulder separation, including a heavy delay to his trigger after foot strike. There is a potential issue here, as the combination of a big reverse-twist of the upper half with a heavily-delayed trigger leaves the pitcher at risk of elbow drag, in which the throwing elbow lags behind the shoulder line (imagine a broomstick across the pitcher’s shoulders) during key parts of the process that accelerates the throwing arm. Pitchers with elbow drag, especially those that throw hard, are at an elevated risk of elbow injury; of course, Giolito has already had Tommy John surgery, so maybe I’m stating the obvious.

His repetition isn’t as bad as the big-league walk rate suggests, but he doesn’t hit that many targets, either. Giolito does a good job of repeating some of the stability aspects of his delivery, resulting in an arm slot that is reasonably consistent, but his coordination of the rotational aspects needs some fine-tuning. The arm will be late (particularly from the stretch) and the arm will be early, resulting in some ugly misses that batters spit on early in the flight path. He uses a slide step from the stretch – a necessary move given the slow pace of his windup – in which Giolito essentially picks his foot up and gets right into the late-burst portion of his momentum. He is such a young pitcher with such disparate timing patterns between windup and stretch – neither of which he has mastered – that the developmental hurdles he still needs to clear makes one wonder just how much effectiveness he loses from the windup to the stretch, and whether that’s worth the trade-off.

There has been some talk about how the Nats sought to adjust Giolito’s mechanics earlier this season in the minors, but supposedly the mechanical tweak didn’t take and the right-hander reverted back to his old delivery. His numbers support the narrative that he struggled with the adjustment and that things have been fine since he changed back, but there has to be at least some concern when the organization sees a mechanical flaw that they want to address yet the player is unable to handle the adjustment. I think that Giolito still has a lot to learn before he is ready for the majors, but that he could be dominant once he has harnessed his delivery and his stuff.

Thank you for reading

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Doug, great work as always. Any plans for one of these on Glasnow? Although, with the shoulder bothering him against the Phillies it might not be worthwhile. It just shows us fans that just because a player is a top prospect, it doesn't mean that he is ready to contribute in MLB.