Tyler Glasnow will serve as the domino for the 2018 Pittsburgh Pirates pitching staff

With the additions of Joe Musgrove and some legitimate bullpen arms, the Pittsburgh Pirates will have some choices to make with their 2018 pitching staff. One player in particular may end up dictating those decisions.

It’s hard to imagine a Pittsburgh Pirates pitching prospect that had more fanfare surrounding his debut than Tyler Glasnow.

Having dominated minor league hitters, Glasnow’s arrival was set to begin a new era in Pirates baseball. Along with Jameson Taillon, the tall right hander would lead the team’s rotation for years to come.

Fast forward to today, and the jury is firmly out on Glasnow. His ultimate destination is unclear. He may win the last spot in the Pittsburgh Pirates starting rotation, he may be relegated to the bullpen or perhaps even start the season back at an old haunt with Triple-A Indianapolis.

Regardless of where he pitches, Glasnow will need to show an ability to deceive hitters. After posting gaudy strikeout totals at every minor league level he has stopped at, Glasnow has yet to figure out how to punch out major league hitters with any level of consistency.

It all stems from having deceptive stuff, and Glasnow actually took a step back in that regard during the 2017 season:

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Here, O-Swing is defined from FanGraphs as the percentage of pitches swung at by opposing hitters that land outside of the strike zone. Glasnow took a step back here, though only a two percentage point drop. However, his paltry mark of 25 percent becomes magnified when considering that 30 percent is the accepted league average. Much has been made about Glasnow’s need to develop his changeup. Clearly he felt a bit more comfortable with it in 2017, having thrown it 12.44 percent of the time as opposed to 2.53 percent the year before, but the right-hander was only able to generate 22 swings and misses out of 132 changeups thrown.

The same was true for Glasnow’s curveball, which only generated 40 whiffs out of 278 total curves thrown. This all adds up to a sub-par SwStr (swinging strike) percentage. It also means that the once-darling Pittsburgh Pirates prospect only starts off 56.7 percentage of his PAs against him with a strike (F-Strike %).

Glasnow attempted to compensate by adding a pitch with more movement — a two-seam fastball with sinking movement — but clearly that did not work as intended.

Regardless of what Glasnow does to improve his performance at the MLB level in the upcoming season, he still serves as a domino that needs to fall before many other roster decisions can be reached.

As the big guy goes…

If the Pittsburgh Pirates see something they like in Glasnow’s spring performances, they may be tempted to give him another crack at the starting rotation. Doing so would put Joe Musgrove in the bullpen and likely bump someone like Steven Brault to Triple-A as the team’s first starting pitching depth option. Such a decision may come down to how the ball looks coming out of Glasnow’s hand as well as his mechanics. Grapefruit League results won’t come into play for two reasons. The first is because they absolutely shouldn’t and anyone that tells you differently is wrong. The second is that the club has likely learned its lesson from Juan Nicasio‘s 2016 spring that saw him surprisingly take a starting rotation spot. By the time the Pittsburgh Pirates realized their mistake and put Nicasio back into the bullpen where is most effective, Nicasio’s 2016 season had already gotten off on a sour note.

With Michael Feliz, George Kontos and Daniel Hudson serving as locks to make the club’s relief unit, there are not too many spots left in a relief unit that is loading up on strikeout ability. Could Glasnow end up there? As we saw above, what has Glasnow shown that tells us he can get batters to swing and miss consistently? Not much, and putting Glasnow on the 25-man in a relief spot might be counter-productive to the Pirates’ quest for relief punchouts.

Doing so would not only create a logjam in terms of bodies but also in terms of philosophy. Manager Clint Hurdle is still somewhat of an old-school bullpen manager, and prefers to have his relievers in set roles. Presuming that Glasnow in the bullpen ensures Musgrove a starting spot, Brault will once again likely be on the outside looking in. This sets Glasnow up to be a long-man or high-leverage reliever. But the issue that stems from trusting Glasnow in either of those roles stems from his second best pitch — his curveball.

We’ve seen above that Glasnow’s curveball isn’t quite ready for prime-time, as it can’t generate a necessary volume of swing and miss. With a changeup that we can generously describe as a work in progress, Glasnow will have to rely on  that two-seam/sinking fastball which is also lagging behind his dazzling four-seamer. When Glasnow made relief appearances towards the end of the 2017 season, the pitch was nearly absent completely, leaving just his changeup to go along with the straight heat. Glasnow is prone to control issues with his best pitch as well, so relying on the changeup as a foil when he has control problems is a non-starter.

So is Indianapolis the best bet? And what happens then?

The Pittsburgh Pirates may in fact punt and send Glasnow to Triple-A Indianpolis to serve as a depth option and continue to refine his secondary pitches. To do so would open up Brault to serve as the team’s primary long relief option.

The team might also feel this is the best option for Glasnow rather than to further erode his confidence should he be unable to get hitters out consistently in a bullpen role.

Should he start in Indianapolis, the resulting time away from the big league club allows the chance for the very same names we’ve mentioned here — Musgrove, Brault, etc — to solidify their roles, making it harder for Glasnow to break back into the big leagues aside from injury.

The baseball season is a long one, and chances are that Glasnow will be heard from in the major leagues for a considerable amount of time in 2018. However, it’s hard to recall one player having this much impact on so many potential roster decisions.

That’s exactly what the Pittsburgh Pirates have laid out before them, and for the team to have any serious aspirations to “surprise” as they did in 2013 (in Neal Huntington’s words), they will have to see some meaningful contribution from one of their most talented hurlers.

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