Tampa Bay’s Blake Snell entered the season as one of Major League Baseball’s top prospects. Among the top-20 names on a number of the industry’s preseason lists and a dark-horse Rookie of the Year Candidate, there were rumors that the young left-hander might agree to a contract extension with the Rays that likely would have placed him on the club’s Opening Day roster. That didn’t happen, however. Finally, after sufficient time had passed to secure an extra year of service time for the Rays, Snell was called up to make a start and pitched well. Following that, however, a series of off days allowed Tampa Bay to deploy a four-man rotation. That, combined with a series of solid starts from Matt Andriese, meant Snell stayed down in the minors. Now he’s back and the results so far are mixed — but also easily corrected.

When a pitcher has compiled just three starts in the majors, and the first one of those is separated by more than a month from the other two, evaluating his statistics is a glass-half-full-half-empty situation. If you want to believe Blake Snell is doing well, look at his ERA and FIP — they’re 2.40 and 2.92, respectively — and how he has yet to concede a home run. For those who’d like to view the glass as half empty, consider instead that Snell has allowed five unearned runs for which his ERA (by definition) doesn’t account — and that, in his last two starts, he’s recorded as many walks as strikeouts. While giving up no home runs is good, it likely can’t continue like that and could lead to higher run totals in the future.

Digging even a little bit deeper leads to more of the same. His .340 BABIP seems like due (in part) to bad fortune, and his left-on-base percentage at 62.5% would appear to be a further reflection of that bad luck. As nearly two months passed between Snell’s first start and his second start, it might be helpful to parse down even further. Snell’s first start was very much a success. He went five innings, recording six strikeouts and one walk, yielding only one run. In his second and third starts, Snell averaged five innings, too, but fared less well, allowing eight total runs on a 6:6 strikeout-to-walk ratio. While it might be a bit presumptuous to distill the troubles of his more recent appearances to just one variable, there does appear to be a distinct difference between the effective and ineffective versions of Blake Snell. The lesson one learns: getting strike one is very important for him.

After Snell’s first start, Jeff Sullivan wrote about Snell’s extreme “rising” fastball. That fastball is still there, and it is still pretty extreme when it comes to vertical movement. Here it is in his last start against Jason Kipnis:

This at-bat was always going to be difficult for Kipnis: not only did he lack the platoon advantage but was also forced to contend with shadows that can make it difficult to pick up the ball. Snell took advantage, but put very few balls in the strike zone. He eventually got the strikeout, but it took some effort, and if you look at the FOX strike zone in the .gif above, it’s pretty clear that Snell was not pitching in the strike zone. This approach can work, but it’s a difficult one to sustain — and leads to higher pitch counts — if hitters begin to exhibit some patience.

Over his first three starts, Snell’s PITCHf/x zone percentage is 47%, a figure that’s been fairly uniform in each of his starts. That number itself isn’t necessarily poor. The league-average mark is 48% and other lefties like Madison Bumgarner, Cole Hamels, and Dallas Keuchel are all below that mark. In other words: overall zone rate doesn’t necessarily equate to success. If we’re looking for a difference from Snell’s first start to his second start, strike one is the important figure.

Blake Snell First Strike Percentage By Start Date F-Strike% 4/23 68.4% 6/16 42.9% 6/21 44.8%

Here’s the chart from Brooks Baseball with the pitch count in the at-bat. Notice all of the “1” boxes that are above the strike zone. Those are chase pitches, but thrown in a non-chase count.

League average for first-strike percentage is 60%, and some of the same guys who’ve recorded low zone percentages like Bumgarner and Zack Greinke and Madison Bumgarner have nevertheless also produced some of the league’s highest first-strike percentages. The lowest first-strike percentage in the majors among qualified pitchers belongs to Carlos Rodon, at 52%. Only seven of 96 pitchers have recorded marks below 55%. It’s very hard to be successful without getting strike one.

While this might be old hat for some, looking at the relationship between count and production bears some fruit here. Consider: after a 1-0 count, hitters are putting up a .269/.380/.452 line on the season, per Baseball-Reference. After an 0-1 count, on the other hand, hitters are putting up a line of just .221/.264/.347 line, a massive difference — especially when it comes to on-base percentage. The counter to that might be that being aggressive in the zone on the first pitch will lead to more first-pitch hits. After all, on plate appearances on the first pitch, hitters are hitting .349/.355/.387. While true, those plate appearances account for just 39% of plate appearances when the batter swings at the first pitch, and the OBP when swinging on the first pitch is about 40 points lower (.290 to .332) compared to when the hitter takes the first pitch. Out of roughly 80,000 first pitches this year, there have been just 2,996 hits (3.7%) and just 1100 extra-base hits (1.4%).

By getting ahead in the count, either with his fastball, changeup, or a throw-me-over curve, Snell puts himself in good position the rest of the at bat. This is particularly true against righties, where he can put them away with that change, like he did here against Carlos Santana.

In the at-bat above, Snell put four of five pitches in the zone, wasting only an 0-2 curve in the dirt. He threw three changes in the strike zone, getting two swings and misses and a called ball that could have been a strike. Snell got hit around in his second start, but with nine ground balls, one fly ball, and four line drives, it’s not as though he was obviously conceding loud contact.

Given the damage they can do on batted balls, challenging the best hitters in the world represents probably one of the more difficult aspects of the jump to the majors — particularly for pitchers who’ve been able to overwhelm minor-league opponents merely by virtue of premium stuff. Snell appeared to have a good game plan against the Yankees and got positive results. He backslid a little in his last two starts, but by emphasizing strike one, he will likely continue to improve. That’s the glass-half-full view, at least.