Strikeout Rate Risers and Fallers - Buy or Sell for Week 13

June 24, 2019

Connelly Doan identifies pitchers whose impressive and underwhelming strikeout rates could make them worth adding or dropping in fantasy baseball for Week 13.

Welcome back to the strikeout rate risers and fallers series for (hopefully) lucky Week 13! Each week we will take a look at two K% risers and two fallers, analyze what is behind those changes, and then decide if they are actionable. A pitcher can best control their fate by generating swings and misses, so this exercise holds particular importance for fantasy value. Understanding strikeout trends and the stats behind them can help you sort through all the noise and determine which pitchers are legit and which pitchers should be avoided.

The players in this article were chosen using RotoBaller’s K% Risers and Fallers premium Tool. This tool identifies players who are surging and falling in strikeout percentage over the last 30 days. The goal of this tool is to help you find pitchers who are showing improving or declining K%.

As we near the All-Star Break, fantasy players will need to assess if their teams are ready for the second half playoff push. Having a solid starting rotation of reliable pitchers is key to a competitive team, so now is the time to take advantage of deals. Let's take a look at two K rate risers and fallers to try to aid in that process!

Strikeout Rate Risers

All stats current as of Sunday, June 23

Wade Miley - Houston Astros

Season K%: 20.5%, Last 30 Days: 30.4%

Our first K rate riser made the list a few weeks ago and is now the top K rate riser for the week. Wade Miley found success in 2018 with the Brewers after several seasons of mediocrity, thanks to the introduction of the cutter into his arsenal. This trend has followed him into 2019, as he has compiled a 6-4 record with a 3.51 ERA, 1.19 WHIP, and a respectable 20.5% K rate. That mark has rocketed to a stellar 30.4% in the last 30 days. What is going on with Miley's strikeout numbers?    

Two things stand out in terms of Miley's recent spike in K rate. The first is his mix of pitches. Miley has relied almost exclusively on a fastball-changeup combination in June (59.4% combined usage of cutter and four-seamer, 24% changeup usage) and it has been keeping hitters off balance. Miley has been pitching smart, making his non-overpowering pitches better than they are thanks to deception. His swinging-strike rates on his fastballs are decent but not great (9% for cutter, 7.2% for four-seamer), but his changeup has been a great swing-and-miss pitch (19.7% swinging-strike rate).

Miley's change of speeds has helped him rack up strikeouts over the past 30 days in tough matchups. He posted eight strikeouts against the Red Sox, nine strikeouts against the Cubs, and seven strikeouts in his most recent start against the Yankees on the road. I think that there is enough evidence now to suggest that Miley's revival is legit and that he can be a huge fantasy value given where he was being drafted. He is currently just 59% owned, so if you are a fantasy owner looking for a final piece to bolster your roster for the second half, go get him now!

Walker Buehler - Los Angeles Dodgers

Season K%: 28.4%, Last 30 Days: 34.8%

The first K% riser has been a phenom since he joined the Show last season. Walker Buehler has been a top-end fantasy starter again this season, posting a 2.96 ERA, 0.86 WHIP, and 100 strikeouts over 91 1/3 innings pitched. His K rate over the past 30 days has been even better at 34.8%. Let's take a look at how he has found his success.  

Buehler has an impressive arsenal of pitches which help him rack up strikeouts. His fastball velocity (96.6 MPH) and spin rate (2,445 revolutions per minute) both sit in the top-10 percent of the league. Further, the spin he gets on both his slider and curveball make the pitches great swing-and-miss options (18.4% and 19.1% swinging-strike rates, respectively). The 24-year-old is able to command the strike zone well (0.86 WHIP, 3.7% walk rate), making his arsenal that much more effective.

Buehler's spike in K rate over the last 30 days can be attributed to several stellar performances. He has a nine-strikeout, 11-strikeout, and 16-strikeout game in his last six starts. While these kinds of performances are not all that common, Buehler is simply a great young talent. He should continue to be a top strikeout pitcher throughout the season and is a fantasy stud.

Strikeout Rate Fallers

All stats current as of Sunday, June 23

Blake Snell - Tampa Bay Rays

Season K%: 32.6%, Last 30 Days: 24.6%

Our first K% faller has been suffering a hangover following his Cy Young season in 2018. Blake Snell has been pedestrian in 2019 after an incredible performance last season, posting a 4.40 ERA and 1.24 WHIP over 75 2/3 IP. The strikeouts have been there (32.6% K rate), but that mark has dropped quite a bit in the last 30 days. Should fantasy owners be concerned with their ace based on his performance so far?

Snell's drop in K rate over the past 30 days can be attributed so some pretty atrocious starts. He did not make it to the fifth inning in half of his last six starts, including his most recent start against the Yankees in which Snell managed to get a single out before receiving the hook. His command over the past 30 days has been off; both his WHIP (1.69) and walk rate (13.1%) have been significantly higher than his season marks of 1.24 and 9%. The good thing is that Snell is much better than this and it is unlikely that he will repeat a string of starts this bad.

There are actually some good underlying signs for Snell despite his overall numbers. First, Snell's pitch arsenal is still as dirty as ever. His fastball velocity and spin rate are in the 88th and 75th percentiles of the league and his swinging-strike rate on the season is an impressive 18.3%. Second, Snell's batted-ball profile is strong (87.2-MPH average exit velocity, 29.4% hard-hit rate, 12.1-degree launch angle), yet his .329 BABIP is much higher than his .289 career mark, suggesting positive regression. Finally, his 3.49 SIERA is much better than his ERA.

Snell has all the makings of a great buy-low candidate. His advanced stats suggest that he is fine, but all owners are probably thinking about is his last abysmal start. Now is the perfect time to make an offer for him and pick up a starter who could carry your team in the second half.

Julio Teheran - Atlanta Braves

Season K%: 21.2%, Last 30 Days: 14.7%

I wrote about Julio Teheran a few weeks ago in the strikeout fallers column and he finds himself here again. He has had a great start to the season, going 5-5 with a 3.40 ERA, 1.26 WHIP, and 21.2% K rate. However, Teheran's K rate has dropped even further to a poor 14.7% in the last 30 days. I said that Teheran was a sell-high candidate last time I wrote about him; have things changed?

Teheran is still presenting conflicting signals that make me question his success. He has a 2.56 ERA and 1.23 WHIP over his last six starts. However, his command has still been an issue. Teheran has 17 walks in that time and a bloated 5.75 SIERA. He doesn't have overpowering stuff, so he needs to have control of his command to be successful.

Teheran has managed to be successful despite having a lack of command (11.5% walk rate). His SIERA and BABIP (.245 vs .267 career) suggest that he has been getting lucky. I don't believe that Teheran can continue his success given his performance and I still believe that he is a strong sell-high candidate.

K-Rate Risers and Fallers - Premium Tool

Identifying top strikeout rate risers and fallers for each week can help you spot the best pickups before your competition. RotoBaller's Premium K-Rate Risers and Fallers tool has you covered every day. As thoughtful fantasy baseball players, we won't lead you astray. This tool will soon be active once we have a large enough sample size in the season to be considered reliable.

This type of data is available as part of our Premium MLB Subscription. Don't settle for basic stats and surface-level advice from other sites. RotoBaller brings you advanced statistics and professional analysis that you need to win your fantasy leagues and DFS games, because we're ballers just like you. We are your secret weapon!

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